Anion Exchange Membrane Based on Poly (2, 6-dimethyl-1,
4-phenyleneoxide) with Pendant Groups for Improved Hydroxide
Conductivity and Chemical Stability
Zhengjin Yanga, Jianqiu Houa, Tongwen Xua
CAS Key Laboratory of Soft Matter Chemistry, Collaborative Innovation Center of Chemistry for Energy Materials, School of Chemistry and Material Science, University
of Science and Technology of China, Hefei 230026, P.R. China [email protected]
ABSTRACT
For anion exchange membranes, the requirement for efficient hydroxide
conductivity but without excessive hydrophilicity presents a challenge. Hence, new
strategies for constructing mechanically strengthened and hydroxide conductive
(especially at controlled humidity) membranes are critical for developing better AEMs.
We report macromolecular modification involving ylide chemistry (Wittig reaction) for
the fabrication of novel AEMs with interpenetrating polymer network (IPN) structure.
The macromolecular modification is a cost effective, facile and is based on a one-pot
synthesis. AEM water uptake was reduced to 3.6 wt % and high hydroxide conductivity
(69.7 mS/cm, 90 oC) was achieved simultaneously. More importantly, the membrane
exhibited similar tensile strength (> 35 MPa) and comparable flexibility in both dry and
wet state.
In the meantime, we use Suzuki-Miyaura coupling reaction to construct anion
exchange membranes with pedant functional groups. The introduction of pedant type
functional groups will facilitate the formation of phase-separated morphology. Anion
exchange membranes with hydroxide conductivity and water resistance could be
obtained. Moreover, the reactions used in this work are easy to carry out. The lack of
water dependence on the performance of the resulting membrane offers promise for
future academic and industrial investigations. High hydroxide conductivity is
particularly promising for AEMFC utilization. Our strategy for decoupling the
conductivity-water resistance dilemma appears successful and form the basis for future
studies. Industry trials based on these novel membranes are anticipated due to their
cost-effectiveness and easy operation.
REFERENCES
[1] Yang, ZJ, Xu TW* et al. Macromol. Rapid Commun., 2015, 36,1362.
[2] Yang, ZJ, Xu TW* et al. J. Mater. Chem. A, 2015, 3, 1501.
P2-1
Preparation of Non-Stacked Reduced Graphene Oxide
Hydrogel Film with a Continuous Ion Transport Network for Supercapacitors
Lifeng Yan*, Xiayu Feng, Wufeng Chen
Department of Chemical Physics, University of Science and Technology of China. Hefei, 230026, P.R. China,
[email protected] ABSTRACT
As a famous star of carbon family, graphene has been actively investigated for
supercapacitor applications for its high theoretical surface area (2630 m2 g-1), excellent
electrical conductivity and chemical stability, and various types of graphene based
materials have been reported for their application as supercapacitor electrodes. However,
the surface areas of graphene derived from graphene oxide (GO) were low and far below
the theoretical value due to the stacking of GO/rGO nanosheets, and it is necessary to
develop new method to fabricate graphene electrodes having a high surface area with
higher pore volume.
The ion diffusion and adsorption in carbon materials are highly sensitive to pore size,
surface wettability, and the pore interconnectivity. So the packing density of graphene
materials is a key factor needed to be controlled. Generally, graphite is highly compact
conductive carbon materials with a packing density of about 2.2 g cm-3 in the ambient
condition, and most ions cannot access the interplanar space, result in poor energy
storage capacitity. Therefore, it is very important to make non-stacked graphene materials
as electrodes for supercapactiors.
One key point for the nano-stacked graphene preparation is preventing the collapse of
the GO architecture during reduction due to the increasing of hydrophobicity of the
as-fromed rGO nanosheets. In addition, the homogeneous reduction is also important to
preserve a highly electrical conductivity. In situ reduction in the wet state under mild
condition will be best. Here, a hydrogel film of GO were prepared at first by filtration of
the GO aqueous suspension, and the hydrogel film was then directly reduced by
electrochemical method to remain its ions channels and highly specific surface area, and
the as-formed electrochemical reduced GO film (ERGO) was directly used in wet state as
the electrodes for supercapacitors. A high performance of supercapacitor was achieved.
REFERENCES
[1] Yang,X; Zhu,J; Qiu,L; Li,D. Adv. Mater., 2011,23, 2833.
[2] Zhu,Y.W.; Murali,S.; Stoller, M. D.; Ganesh, K. J.; Cai, W. W.; Ferreira, P. J.; Pirkle
A.; Wallace, R. M.; Cychosz, K. A.; Thommes, M.; Stach, E. A.; Ruoff, R. S.; Science
2011, 332, 1537
[3] Feng, X.Y.; Chen, W.F.; Yan, L.F. Nanoscale 2015, 7, 3712.
P2-2
Direct In Situ Observation and Explanation of Lithium Dendrite of
Commercial Graphite Electrodes
Zhansheng Guoa, Jianyu Zhua, Jiemin Fengb
a Shanghai Institute of Applied Mathematics and Mechanics, Shanghai 200072, China
b Department of Mechanics, College of Science, Shanghai University, Shanghai 200444, China
ABSTRACT
Lithium-ion batteries (LIBs) have some serious safety problems, such as lithium
dendrite formation during charging/discharging cycles that may cause internal
short-circuiting, catch fire, and even explode. A new double scale in situ experimental
setup which can capture all phenomena during the electrochemical testing was
developed. Lithium dendrite growth behavior of commercial LIBs during small current
density charging at room temperature was observed in situ. The formation, growth,
dissolution of lithium dendrite and dead lithium residue were all observed and recorded
by this new experimental test system. A detailed model of lithium electrodeposition and
dissolution processes was proposed. The electrode structures were determined by X-ray
diffraction (XRD). The surface morphology was measured by scanning electron
microscopy (SEM). The texture and surface morphology of graphite active layer have
affected lithium dendrite initiation as well as its growth processes.
P2-3
Effect of Mg-doping on the structure and Electrochemical
Performances of Co-free Li-rich layered Cathodes Jianming Fana, Guangshe Lia, Dongjiu Xiea, Guohua Lia, Liping Lia,*
a Key Laboratory of Design and Assembly of Functional Nanostructures, Fujian
institute of research on the structure of mater, Chinese Academy of Sciences, Fuzhou
350002 , P. R. China
ABSTRACT
In response to the needs of lithium ion batteries with high energy density and low
cost, intense explorations for better cathode have long been focused on lithium-rich
layered oxides (LLOs).[1] The high energy density of LLOs is attributed to the Li2MnO3
component with C/2m structure that usually would be activated over 4.5 V.
Unfortunately, during the first high-voltage charge process, the deintercalation of excess
lithium ions in transition metal layer creates vacancies. Moreover, the loss of oxygen
ions also occurs. Both of these variations would lead to a structural transformation from
layer to spinel in the following charge-discharge cycling, accompanied with voltage
decay, [2] which in turn causes a reduced energy density and difficulty in determining the
state of charge of battery cells. Cation doping could alter the chemical bonding of
transition metal-oxygen, and further improve stability of layer structure, which
effectively block the layer-to-spinel transformation. Among various cation doping,
Mg-doping was found to have the better performance. [3] But intrinsic mechanism is still
uncovered.
Herein, we prepared Mg-doped Li1.2Mn0.6Ni0.2O2 by a combined sol-gel and
high-temperature calcination method. X-ray diffraction (XRD), Scanning electron
microscopy (SEM), X-ray photoelectron spectroscopy (XPS), adiabatic rate calorimetry,
galvanostatic charge-discharge measurements and electrochemical impedance spectroscopy
(EIS) are employed to determine the crystal structure, particle morphology, thermal
stability and electrochemical performance of Li1.2Mn0.6-xMgxNi0.2O2,
Li1.2Mn0.6Ni0.2-xMgxO2 and Li1.2-xMgxMn0.6Ni0.2O2 (x = 0.1, 0.2, 0.3, 0.4). Substitution
of Mg ions for transition metal ions improves rate-capability slightly, but sacrifices
capacity. Comparatively, Doping Mg ions at Li sites could inhibit voltage decay, and
enhance structural stability as well as rate-capability. The relationship of lattice structure,
valence state and electrochemical performance were revealed.
REFERENCES
[1] Fan, J. M.; Li, G. S.; Luo, D.; Fu, C. C.; Li, Q.; Zheng, J.; Li, L. P.. Electrochim.
Acta 2015, 173, 7.
[2] Li, Q.; Li, G.; Fu, C.; Luo, D.; Fan, J.; Li, L.. ACS Appl. Mater. Interfaces 2014, 6,
10330.
[3] Wang, Y. X.; Shang, K. H.; He, W.; Ai, X. P.; Cao, Y. L.; Yang, H. X.. ACS Appl.
Mater. Interfaces, 2015, 7, 13014.
P2-4
Three-Dimension Nanoporous Graphene-based Materials and Its Applications
Liang Chen1, Tao Yi1,*
Fudan University, 220 Handan Road, Shanghai 200433, China. [email protected]
ABSTRACT
Graphene material is one of the hot research fields in the physics, chemistry and
material science, and has potential use in information, energy storage and nanoscale devices due to their unique structure and physical chemistry properties. However, the strong van der Waals and π-π stacking interactions between graphene sheets make them readily aggregate to form graphite-like powders or films with dense layered microstructures, which inevitably decrease their effective specific surface area and electric conductivity, and actually reduce their use value. Therefore, to amplify the intrinsic properties of graphene, it’s stacking needs to be effectively prevented. Aimed at this target, our group skillfully using the self-assembly methods to assemble the 2D graphene sheets into 3D column network structure, the stacking of graphene can be effectively restrained consequently. As a result, the surface area and conductivity of these graphene materials greatly improved. In addition, when adding appropriate nitrogen and sulfur sources into the graphene matrix, a series of versatile, doped graphene materials have been achieved after heat treatment, including 1) 3D nitrogen-doped graphene nanoribbons aerogel; 2) three-dimensional nitrogen doped carbon nanoleaf networks; 3) intrinsically coupled 3D nano-graphene sheets@carbon nanotube (nGs@CNTs) frameworks. Meanwhile, the oxygen reduction reaction (ORR) and lithium ion batteries (LIBs) performances by using those materials were also revealed. Experimental results show that these 3D nanoporous graphene-based materials possess an ideal interconnected network and high electronic mobility. When using as ORR catalysts, it exhibited excellent electrocatalytic activities for ORR, which is one of the best among all the graphene-based oxygen reduction catalysts reported previously. On the other hand, when using as anode materials in LIBs, it can deliver high reversible capacity with excellent cycling performance.
References:
[1] Chen, L.; Jin, X.; Wen, Y.; Lan, H.; Yu, X.; Sun, D.; Yi, T. Chem. Mater. (In version) [2] Chen, L.; Xu, C.; Du, R.; Mao, Y.; Xue, C.; Chen, L.; Qu, L.; Zhang, J.; Yi, T. J. Mater. Chem. A., 2015, 3, 5617. [3] Chen, L.; Du, R.; Zhu, J.; Mao, Y.; Xue, C.; Zhang, N.; Hou, Y.; Zhang, J.; Yi, T. Small 2015, 11, 1423.
P2-5
1st International Symposium on Energy Chemistry & Materials, Oct. 29‒31 2015, Fudan University, Shanghai, China
Dual Hybrid Route Towards Enhancing Lithium Storage Performance
of ZnO Hollow Microspheres Qingshui Xie, Yating Ma, Laisen Wang and Dong-Liang Peng*
Fujian Key Laboratory of Advanced Materials, Collaborative Innovation Center of Chemistry for Energy Materials, Department of Materials Science and Engineering,
College of Materials, Xiamen University, Xiamen 361005, China *Corresponding author: [email protected] (D.-L. Peng)
ABSTRACT
Rechargeable lithium ion batteries have been considered as one of the most
promising energy storage devices due to their high energy density, light weight, long
cycling life and so on [1]. However, the low theoretical capacity of the commercial
graphite anode (372mAh g-1
) largely limits its further potential applications in high
energy consumption area. ZnO, as a member of transition metal oxides family, has the
merits of large specific capacity, low cost and environmental benignity, which has been
regarded as the promising anode candidate [2]. Unfortunately, ZnO anode demonstrates
rapidly capacity fading and poor cyclability, resulting from the large volume expansion
along with the intrinsic poor electronic conductivity during lithiation/delithiation
process.
In this paper, a dual hybrid strategy has been introduced to effectively overcome
the two above-mentioned drawbacks of ZnO electrodes through co-hybridizing ZnO
hollow microspheres with metal cobalt and carbon. When applied as the anode materials
for lithium ion batteries, the prepared ZnO-Co-C hybrid hollow microspheres manifest a
high reversible capacity of 623 mA h g-1
at 200 mA g-1
after 200 cycles. The outstanding
lithium storage properties of hybrid microspheres are ascribed to the decoration of
cobalt and carbon, the nanometer-sized building blocks together with the inner hollow
structures of microspheres.
REFERENCES
[1] Tarascon, J. M.; Armand, M. Nature 2001, 414, 359.
[2] Huang, X. H.; Wu, J. B.; Lin, Y.; Guo, R. Q. Int. J. Electrochem. Sci. 2012, 7, 6611.
P2-6
Self-assembled birnessite MnO2 nanostructures for electrochemical capacitive energy storage
Yu Xin Zhanga, b, Shi Jin Zhua, Min Kuanga
a College of Materials Science and Engineering, Chongqing University, Chongqing
400044, b National Key Laboratory of Fundamental Science of Micro/Nano-Devices and System
Technology, Chongqing University, Chongqing, 400044 E-mail: [email protected]
ABSTRACT We would like to introduce the self-assembly of MnO2 nanostructures with controllable morphology for electrochemical supercapacitor, including carbon@mesoporous MnO2 coaxial nanotubes, CeO2/MnO2 nanostructures, MnO2-Cu2AlO4-Ni foam nanostructures. Noteworthily, it is the first time to synthesize birnessite-type MnO2 nanosheets-interwoven/amorphous-carbon nanotubes, exhibiting high specific capacitance (362 F/g) and better cycle stability. Moreover, CeO2@MnO2 core-shell architectures were obtained through self-assembly, presenting unprecedented pseudocapacitance performance with outstanding rate capability. Besides, hierarchical MnO2-CuCo2O4 core-shell arrays on Ni foam were designed with binder-free strategy. In principle, we have reported the successfully self-assembly of MnO2 into various controllable morphology with different templates. It is believed that fabrication of these nanostructures will provide new and facile approach to fabricate high-performance electrode for supercapacitors. [1-3]
Figure 1 Typical images of our MnO2 nanostructures. REFERENCES [1] Zhu, S.J., Zhang, Y.X.* et al. J. Power Sources. 2015, 278, 555-561. [3] Zhu, S.J., Zhang, Y.X.* et al. Chem.Comm. 2015, DOI: 10.1039/c5cc03976b. [3] Kuang, M., Zhang, Y.X.* et al. J. Mater Chem A, 2015, In revision.
A1
A2
B1
B2
C1
C2
P2-7
Tantalum-doped lithium titanate with enhanced performance for
lithium-ion batteries
Min Guoa, Suqing Wanga*, Liang-Xin Dinga, Haihui Wanga,b* a School of Chemistry & Chemical Engineering, South China University of Technology,
Wushan Road, Guangzhou 510640, China b School of Chemical Engineering, The University of Adelaide, Adelaide, SA 5005,
Australia [email protected], [email protected].
ABSTRACT
As an alternative to current carbon-based anodes, Li4Ti5O12 (LTO) shows promising electrochemical properties. It is a zero-strain insertion material and has a flat and relatively high voltage plateau (~1.55 V vs. Li/Li+).[1] But its poor electronic conductivity hinders the practical applications on high power devices. Ion doping is an effective method to improve the rate capabilities of LTO owing to the significant effects of the metal ion dopants on their inner electronic and crystalline structure. Among various doping ions, Nb5+ and Ta5+ with a valence 5+ and similar ionic radii as Ti4+, are considering to be reasonable solubility in Ti sites. Hence, substitute a Nb5+/Ta5+ on a Ti4+ site of Li4Ti5O12 might lead to an increase in electron concentration and then increase the electronic conductivity. Our group previously has proved that Nb5+ doped into LTO might make the lattice parameter become larger and form mixed valence (Ti4+/Ti3+) as charge compensation, thus improving the rate capability.[2]
Considering the industrial applications, doping method combined with solid-state method is most easily to industrialization. Herein, we successfully synthesized Ta-doped LTO in oxidizing atmosphere via solid-state reaction. The LTO with only 0.1 at% Ta doping (Li4Ti4.995Ta0.005O12) exhibits higher rate capability and better cyclic stability than the bare LTO. It delivers 95.1 mAh g-1 at 10C with low overpotential (216.1 mV) and delivers a capacity of 132.2 mAh g-1 after 100 cycles at 5C, while the pristine LTO delivers only 50.4 mAh g-1 at 10C. The excellent electrochemical performance of LTO is ascribed to the improved ionic conductivity and electronic conductivity.
Figure 1. (a) Rate capabilities of the Li4Ti5-xTaxO12 (0≤x≤0.05); (b) The cycling
performances at the rate of 5C for the Li4Ti5O12 and Li4Ti4.995Ta0.005O12 electrodes.
REFERENCES
[1] Zhao,L; Hu ,Y. S; Li, H; Wang Z. X; Chen L. Q. Adv. Mater. 2011, 23, 1385. [2] Tian,B.B; Xiang, H.F; Li, Z; Wang,H.H. Electrochim. Acta 2010, 22, 5453.
P2-8
Copper-Tuned Porous Carbon Immobilizing Sulfur as Cathodes for
Li-S and Room Temperature Na-S Batteries
Shiyou Zheng, Tao Yuan, Junhe Yang
School of Materials Science and Engineering, University of Shanghai for Science and Technology, Shanghai 200093, China
ABSTRACT
A copper-tuned porous carbon immobilizing sulfur (PC-Cu-S) composite was
synthesized by uniformly dispersing highly electronically conductive Cu nanoparticles
into porous carbon (PC), followed by wet-impregnating sulfur. The unique
structural PC-Cu-S composite cathode containing 50% S shows stable and high
reversible capacities, together with remarkable rate and cycling capabilities in Li-S and
room temperature Na-S batteries. For instance, in the Li-S cells, the PC-Cu-S
composite cathode allows using a low-cost carbonate electrolyte (1.0 M LiPF6 +
EC/DEC (1 : 1 v/v)), and shows that Coulumbic efficiency is close to 100 % and
capacity maintains more than 600 mAh/g with progressive cycling up to more than 500
cycles at a current density of 100 mA/g; As the cathode for the room temperature Na-S
battery, the cell maintains capacities of around 610 mAh/g with Coulumbic efficiency
close to 100% in 110 cycles at the current density of 50 mA/g, and can provide a
capacity of more than 100 mAh/g even at a high rate of 5.0 A/g. The exceptional
performance of PC-Cu-S cathode is because: (i) Cu nanoparticles chemically stabilize S
to form solid Cu polysulfide clusters through strong interaction between Cu and S; (ii)
Cu nano-inclusins enhance the electronic conductivity of PC-Cu-S cathodes; (iii) PC
host provides free space for volume change of S/polysulfides. The results represent that
small amount of metal nanoparticle tuned PC can substantially stabilize the S cathode,
increasing the S loadings and improving the cycling stability and rate capability.[1]
These encouraging results represent that sulfur molecules binding on Cu-tuned
nanocomposite could be a promising cathode material.
REFERENCES
[1] Zheng, S.; Yi, F.; Li, H. et al. Adv. Func. Mater. 2014, 24, 4156.
P2-9
Cobalt Embedded in Porous Nitrogen Doped Carbon Nanofibers as an
Efficient Bi-Functional Catalyst for Water Splitting
Yufei Zhaoa,b, Kefei Lia, Jinqiang Zhanga, Hao Liua, Kening Sunb, Guoxiu Wanga
aCenter for Clean Energy Technology, School of Mathematical and Physical Science, Faculty of Science, University of Technology Sydney, NSW 2007, Australia
bBeijing Key Laboratory for Chemical Power Source and Green Catalysis, School of Chemical Engineering and Environment, Beijing Institute of Technology, Beijing,
100081, China. [email protected]
ABSTRACT
The major challenge in water splitting is to develop low cost electrocatalysts as
alternatives for simultaneously generating oxygen and hydrogen. Herein, we report the
successful synthesis of cobalt nanoparticles embedded in porous nitrogen doped carbon
nanofibers (Co-PNCNFs) by a facile and scalable electrospinning technology. The
electrospun Co-PNCNFs composite exhibits a low onset potential of 1.45 V (vs. SHE)
along with high current density (overpotential of 310 mV for 10 mV cm-2) towards
oxygen evolution reaction (OER). The exceptional performance could be ascribed to the
bi-functionalized CNFs with nitrogen doping and cobalt encapsulation. The porous
structure and synergistic effect further provide high electroactive surface area and
facilitate a fast electron transfer pathway for the OER process. Interestingly, the
Co-PNCNFs composite also demonstrated a high efficiency for hydrogen evolution
reaction (HER) in both alkaline and acid media. A water electrolyzer cell in alkaline
solution was fabricated by applying Co-PNCNFs as both anode and cathode
electrocatalysts and achieved a high current density of 10 mA cm-2 at a voltage of 1.66 V.
Figure 1. (a, b) SEM and TEM images of Co-PNCNFs. (c) XRD patterns of NCNFs and Co-PNCNFs. (d)
Polarization curves for Co-PNCNFs, NCNFs, Ru/C, Pt/C and pure GC towards OER in 1 M KOH
solution. (e) Stability test of Co-PNCNFs. (f) ) LSV of water electrolysis using Co-PNCNFs as both OER
and HER catalysts. The inset shows the stability test at the potential of 1.66 V over 10 h.
P2-10
1st International Symposium on Energy Chemistry & Materials, Oct. 29‒31 2015, Fudan University, Shanghai, China
Maghemite Embedded Hierarchical Nitrogen Doped Graphene
Framework for Oxygen Reduction Reaction in Alkaline Media
Kaipei Qiua, Chaoran Jiangb, Guoliang Chaia, Junwang Tangb, Zhengxiao Guoa
aDepartment of Chemistry, UCL, 20 Gordon Street, London, WC1H 0AJ, UK
bDepartment of Chem. Engineering, UCL, Torrington Place, London, WC1E 7JE, UK [email protected] or [email protected]
ABSTRACT
During the last several years, increasing research efforts have been made to develop cost-effective and durable electro-catalysts for oxygen reduction reaction (ORR) in aqueous alkaline media.1 The ORR kinetics is faster in alkaline media than in acidic media (i.e. higher exchange current, lower over-potential, and weaker bindings with charged adsorbates) due to the surface-independent outer-sphere electron transfer processes,2 which gives rise to the possibility of using a wide-range of non-noble-metal (NPM) catalysts. Among various types of NPMs ORR catalysts, iron based materials have attracted the most attention. However despite wide ranges of Fe-containing systems have been studied, the real active site and exact reaction pathway of Fe based catalysts still remain elusive.3 Herein we presented for the first time facile synthesis of γ-Fe2O3 embedded hierarchical nitrogen doped graphene framework (γ-Fe2O3@N-GF) which demonstrated comparable oxygen reduction activity with commercial platinum loaded carbon (PtC) in alkaline electrolyte (Figure 1).
Figure 1. Rotating disk electrode (RDE) linear sweep voltammetry (LSV) measurement at 400RPM
in 0.1M KOH for γ-Fe2O3@N-GF and PtC. Insert is the scanning electron microscopy (SEM) image
of γ-Fe2O3@N-GF with energy dispersive X-ray spectrometry (EDX) Fe mapping. REFERENCES
[1] Ge, X. et al. ACS Catal., 2015, 5, 4643.
[2] Ramaswamy, N.; Mukerjee, S. J. Phys. Chem. C, 2011, 115, 18015.
[3] Zitolo, A. et al. Nat. Mater., 2015, 14, 937.
P2-11
Self-templated synthesis of Co3O4 hollow spheres with complex interior
structures and their application to lithium-ion batteries Yating Ma, Qingshui Xie, Laisen Wang and Dong-Liang Peng*
Fujian Key Laboratory of Advanced Materials, Collaborative Innovation Center of Chemistry for Energy Materials, Department of Materials Science and Engineering,
College of Materials, Xiamen University, Xiamen 361005, China *Corresponding author: [email protected]
ABSTRACT
Although metal oxide hollow structures show excellent electrochemical
performance when used as anode materials for lithium ion batteries (LIBs), it is
complex and tedious to tailor the interior structure by template-based multistep
procedures [1]. In this work, we develop a new self-templating strategy to synthesize
Co3O4 hollow spheres with complex interior structures. The final product is prepared by
a simple thermal annealing of cobalt hydroxide precursor which is synthesized via a
mild chemical reaction of cobalt nitrate hexahydrate, sodium tartrate and
hexamethylenetetramine (HMT) in water phase at 90 oC. When used as the anode
materials for lithium ion batteries, Co3O4 hollow spheres with complex interior
structures show excellent electrochemical performance and maintain a reversible
capacity of 762 mA h g-1 at a high current density of 1000 mA g-1 after 500 cycles. The
unique complex interior structure and the porous shells of Co3O4 hollow spheres play an
important role in their excellent electrochemical performance and make them a kind of
promising electrode material for next-generation LIBs [2].
REFERENCES
[1] Wei W, Wang Z, Liu Z, et al. J. Power Sources 2013, 238, 376.
[2] Shen L, Yu L, Yu X Y, et al. Angew. Chem. Int. Ed. 2015, 54, 1868.
P2-12
Anatase TiO2: Better Anode Material than Other Phases of TiO2 for
Na-ion Batteries
Dawei Su, Guoxiu Wang
Centre for Clean Energy Technology, School of Mathematical and Physical Sciences, Faculty of Science, University of Technology, Sydney, NSW 2007, Australia.
ABSTRACT
Recently, Na-ion batteries have been considered as a desirable alternative to Li-ion
batteries due to sodium is substantially less expensive and more abundant than
lithium.[1-5] Tremendous efforts have been used on the development of Na-ion batteries
for large-scale energy storage application. Here we demonstrated the anatase TiO2 is
good candidate as anode material for Na-ion Batteries.
Amorphous TiO2@C nanospheres were synthesized via a template approach. After
being sintered under different condition, two types of polyphase TiO2 hollow
nanospheres were obtained. The electrochemical properties of the amorphous TiO2
nanospheres and the TiO2 hollow nanospheres with different phases were characterized
as anodes for the Na-ion batteries. It was found that all the samples demonstrated
excellent cyclability, which was sustainable for hundreds of cycles with tiny capacity
fading, although the anatase TiO2 presented higher capability than the mixed
anatase/rutile TiO2 and the amorphous TiO2@C. Through crystallographic analysis, it
was revealed that the anatase TiO2 crystal structure supplies two-dimensional diffusion
paths for Na ion intercalation and more accommodation sites. Density functional theory
calculations indicated lower energy barriers for Na+ insertion into anatase TiO2.
Therefore, anatase TiO2 hollow nanospheres show excellent high rate performance.
Through ex-situ field emission scanning electron microscopy, it was revealed that the
TiO2 hollow nanosphere architecture can be maintained for hundreds of cycles, which is
the main reason for its superior cyclability.
REFERENCES
[1]Li, S.; Dong, Y.; Xu, L.; Xu, X.; He, L.; Mai, L. Adv. Mater. 2014, 26, 3358.
[2]Qian, J.; Xiong, Y.; Cao, Y.; Ai, X.; Yang, H. Nano Lett. 2014, 14, 1865.
[3]Sun, Y.; Zhao, L.; Pan, H.; Lu, X.; Gu, L.; Hu, Y.-S.; Li, H.; Armand, M.; Ikuhara,
Y.; Chen, L. Nat Commun. 2013, 4, 1870.
[4]Yabuuchi, N.; Kajiyama, M.; Iwatate, J.; Nishikawa, H.; Hitomi, S.; Okuyama, R.;
Usui, R.; Yamada, Y.; Komaba, S. Nat. Mater. 2012, 11, 512.
[5]Hwang, J.-Y.; Oh, S.-M.; Myung, S.-T.; Chung, K. Y.; Belharouak, I.; Sun, Y.-K.
Nat Commun. 2015, 6. 6865.
P2-13
Improvement of Li1.2Mn0.6Ni0.2O2 Li-rich Cathode by (Na, Al)
Dually-doping with a Superior Cycling Stability at High Temperature
for the Lithium Ion Batteries
Dongjiu xiea, Chaochao Fua, Qi Lia, Jianming Fana, Guangshe Lia, Liping Lia,*
aKey laboratory of Design and Assembly of Functional Nanostructure, Fujian Institution of Research on the Structure of Matter, Chinese Academy of Science, Fuzhou,
35002, P.R. China [email protected]
ABSTRACT
The portable consumer electronics revolution has driven the development of Li-ion batteries for efficient energy storage over the last decade. Currently there is also a strong interest in developing cost—effective, safe lithium ion batteries for long range electronic devices.[1]Due to the higher capacity (>250mAh/g vs Li+/Li) and low cost than the LiCoO2 cathode, Li-rich layered oxides would be a promising cathode material for lithium ion batteries.[2]
However, because of the layered-to-spinel transformation during cycling originated from oxygen loss in the initial charge and strong side reactions with electrolyte at highly delithatied state, Li-rich cathodes show poor capacity retention, hindering their practical application.[3] In this work, dually-doping is designed to improve the electrochemical performance of Li-rich cathode, in which Li+ and Mn4+ ions are partially substituted with Na+ and Al3+, respectively. Accordingly, a series of samples (NaxLi1.2-xMn0.6-xAlxNi0.2O2, X=0, 0.01, 0.02, 0.03, 0.04, 0.05) were synthesized by a simple sol-gel route. Powder X-ray diffraction XRD), Scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), galvanostatic charge-discharge measurements and electrochemical impedance spectroscopy (EIS) are employed to determine the crystal structure, particle morphology and electrochemical performance. The improved cycling performance is observed for the all co-doped samples, among which the sample with x=0.03 exhibits the best discharge capacity retention of 86.1% after 200 cycles between 2.0 and 4.8V vs Li+/Li at a current density of 2C ( 2C=400 mA g-1 ) and excellent cycling stability even at high temperature (55℃) with a capacity retention of 92.2% after 100 cycles. Moreover, comparing to the pristine, the average voltage of the sample with x=0.03 still remains 3.11V vs Li+/Li with a retention ratio of 86.6% after 100 cycles at 0.5C in the range of 2.0-4.8V.
REFERENCES
[1] Patel, P. ACS Central Science 2015,1,161. [2]Thackeray,M.M.;Kang,S.H.;Johnson,C.S.;Vaughey,J.T.; Benedek, R.; Hackney, S. A. J. Mater. Chem.2007,17,3112. [3]Yabuuchi, N.;Yoshii, K.;Myung, S.T.;Nakai, I.;Komaba,S. J Am Chem Soc, 2011, 133, 4404.
P2-14
Tunable Electrocatalytic Hydrogen Evolution Performance by
Tailoring Late Transition Metals in Pt-based Alloy Lattices
Nana Dua, Chengming Wanga, Yujie Xionga
a Hefei National Laboratory for Physical Sciences at the Microscale, School of
Chemistry and Materials Science, University of Science and Technology of China, Hefei, Anhui 230026, P. R. China
ABSTRACT
Pt-based alloy nanostructures are excellent candidates for various electrocatalytic
reactions, whose surface structures and compositions both hold the promise for tuning
their performance. In this communication, we have developed a series of PtFeCo alloy
nanostructures in a TriStar shape with tunable Fe and Co contents for electrocatalytic
hydrogen evolution reaction (HER). The HER performance shows interesting
volcano-type behavior depending on the ratio of Co to Fe. Taken together with the
active surface of TriStar shape, the PtFeCo alloy nanostructures exhibit the enhanced
performance in HER against commercial Pt/C, PtFe nanostructures or other-shaped
PtFeCo nanoparticles.
REFERENCES
[1] Scofield, M. E.; Koenigsmann, C.; Wang L.; et al. Energy Environ. Sci. 2015, 8,
350.
[2] Zhu, H. Y.; Zhang, S.; Guo S. J.; et al. J. Am. Chem. Soc. 2013, 135, 7130.
P2-15
Nitrogen-doped porous carbon derived from residuary shaddock peels:
a promising and sustainable anode for high energy density asymmetric
supercapacitors
Kang Xiaoa, Liang-xin Dinga*, Haihui Wanga,b*
aSchool of Chemistry & Chemical Engineering, South China University of Technology, No. 381 Wushan Road, Guangzhou 510640, People’s Republic of China
bSchool of Chemical Engineering, The University of Adelaide, Adelaide, SA 5005, Australia.
[email protected], [email protected]
ABSTRACT
The hiarchically porous carbon (HPC) is currently an attractive candidate for
supercapacitors, Li batteries, solar cells, and fuel cells. However, despite the ceaseless
development of porous carbons, limited success has been achieved in the synthesis of
HPCs by conventional hard-templating methods. Besides, non-renewable carbon
sources have been utilized for the fabrication of HPCs.[1] In this work, a scalable and
smart approach was developed to transform the crude biomass waste (shaddock peels)
into N-doped porous carbon (NPC) without template or pretreatment process as high
performance negative electrode for ASCs application. The as-obtained NPC with high
surface area, high hierarchical porosity and high N-doping exhibit a remarkable
capacitance of 321.7 F g-1 at a current density of 1 A g-1, as well as excellent long-term
cycling stability. Additionally, a high-performance and flexible ASC devices based on
the as-prepared NPC as the negative electrodes and MnO2 as positive electrodes was
also prepared. The MnO2//NPC-700 ASC device delivered a maximum energy density
of 82.1 W h Kg-1 at a current density of 1 A g-1.
REFERENCES
[1] Wang, G. P.; Zhang, L.; Zhang J. J., Chem. Soc. Rev. 2012, 41.797.
P2-16
P2-17
Nanowire Devices for Electrochemical Energy Storage
Liqiang Mai*
State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Wuhan University of Technology, Wuhan 430070, P. R. China
ABSTRACT
One-dimensional nanomaterials can offer large surface area, facile strain relaxation
upon cycling and efficient electron transport pathway to achieve high electrochemical
performance. Hence, nanowires have attracted increasing interest in energy related
fields.[1-6]
We designed the single nanowire electrochemical device for in situ probing the
direct relationship between electrical transport, structure, and electrochemical properties
of the single nanowire electrode to understand intrinsic reason of capacity fading. The
results show that during the electrochemical reaction, conductivity of the nanowire
electrode decreased, which limits the cycle life of the devices. Then, the prelithiation
and Langmuir-Blodgett technique have been used to improve cycling properties of
nanowire electrode. Recently, we have fabricated hierarchical MnMoO4/CoMoO4
heterostructured nanowires by combining "oriented attachment" and "self-assembly".
The asymmetric supercapacitors based on the hierarchical heterostructured nanowires
show a high specific capacitance and good reversibility with a cycling efficiency of
98% after 1,000 cycles. Furthermore, we fabricated Li-air battery based on hierarchical
mesoporous LSCO nanowires and nonaqueous electrolytes, which exhibits ultrahigh
capacity over 11000 mAh g-1. We also designed the hierarchical zigzag Na1.25V3O8
nanowires with topotactically encoded superior performance for sodium-ion battery
cathodes. Through our study, it will solve the challenge of property degradation and it
may provide extend effect and helpful methods in directions, in energy storage and in
open new applications.
REFERENCES
[1] Niu, C. J.; Meng, J. S.; Wang, X. P.; Han, C. H.; Yan, M. Y.; Zhao, K. N.; Xu, X. M.;
Ren, W. H.; Zhao, Y. L.; Xu, L.; Zhang, Q. J.; Zhao D. Y.; Mai, L. Q. Nat Commun. 2015, 6, 7402.
[2] Zhao, Y. L.; Feng, J. G.; Liu, X.; Wang, F. C.; Wang, L. F.; Shi, C. W.; Huang, L.;
Feng, X.; Chen, X. Y.; Xu, L.; Yan, M. Y.; Zhang, Q. J.; Bai, X. D.; Wu H. A.; Mai, L. Q.
Nat Commun. 2014, 5, 4565.
[3] Qing, Q.; Jiang, Z.; Xu, L.; Gao, R. X.; Mai, L. Q.; Lieber, C. M. Nat Nanotechnol. 2014, 9, 142.
[4] Mai, L. Q.; Tian, X. C.; Xu, X.; Chang, L.; Xu, L. Chem. Rev. 2014, 114, 11828.
[5] Li, S.; Dong, Y. F.; Xu, L.; Xu, X.; He, L.; Mai, L. Q.; Adv. Mate. 2014, 26, 3545.
[6] Yan, M. Y.; Wang, F. C.; Han, C. H.; Ma, X. Y.; Xu, X.; An, Q. Y.; Xu, L.; Niu, C. J.;
Zhao, Y. L.; Tian, X. C.; Hu, P.; Wu, H. A.; Mai, L. Q. J. Am. Chem. Soc. 2013, 135,
18176.
P2-18
Efficient Water Oxidation Catalyzed by Tetraazamacrocyclic Nickel(II)
Complexes: Steric Effects and New Mechanistic Insights
Jia-Wei Wanga, Hai-Hua Huanga, Tong-Bu Lu*
aMOE Key Laboratory of Bioinorganic and Synthetic Chemistry, School of Chemistry and Chemical Engineering, Sun Yat-Sen University, Guangzhou 510275, P. R. China
ABSTRACT
A series of nickel(II)-based macrocyclic complexes with four, six and eight
methyls in ligand structure, have been investigated for their electrocatalytic ability in
water oxidation. The results of electrochemical, spectroscopic and surface analysis
demonstrate that all these complexes are homogeneous electrocatalysts for water
oxidation in aqueous phosphate buffer at pH 7.0. The one with eight methyls in its
ligand structure exhibits comparably excellent efficiency as the published one with six
methyls,[1] maintaining a high current density near 1.0 mA/cm2 in at least 3 h duration
of controlled potential electrolysis at 750 mV overpotential, without any sign of
decomposition. In contrast, the nickel(II) macrocyclic complex with four methyls shows
minor catalytic ability with a moderate current density of 0.35 mA/cm2.
Mechanistic investigations on the three nickel complexes have revealed that steric
strains between axially oriented methyls and axially coordinated OH- at their nickel(III)
state play key roles in their differences among oxidation potentials at NiII/NiIII,
structural distortions and catalytic performances. Based on these results, a more feasible
mechanism of these nickel(II)-based macrocyclic complexes for water oxidation is
proposed below.
REFERENCES
[1] Zhang, M.; Zhang, M. T.; Hou, C.; Ke, Z. F.; Lu, T. B. Angew. Chem. Int. Ed. 2014,
53, 13042.
P2-19
Catalytic Water Oxidation by a Copper Complex with an Unusual
Dependence on Buffer Base Concentration
Hai-Hua Huanga, Jia-Wei Wanga, Tong-Bu Lua*
aMOE Key Laboratory of Bioinorganic and Synthetic Chemistry, School of Chemistry and Chemical Engineering, Sun Yat-Sen University, Guangzhou 510275, P. R. China
ABSTRACT
The Cu-based complex [Cu(meso-L)](ClO4)2 (Figure 1a, inset) exhibits excellent
electrocatalytic activity for water oxidation at pH 7.5, with a sustained current density in
controlled potential electrolysis as high as 1.3 mA·cm-2 at 1.51 V (90% Faradaic yield).
No catalyst poisoning was observed with EDTA addition, suggesting that no copper ion
was released during catalysis.[1] Also, surface analysis showed no deposition of
heterogeneous copper films, indicating homogeneous catalysis.
Kinetic study revealed that the catalytic current density is linearly dependent on
[buffer base]3/2 (Figure 1a), suggesting that the borate buffer not only serves as a proton
acceptor. Density functional computations reveal that two borate anions participate in
the O-O bond formation step (Figure 1b). One borate anion serves as the substrate
which is transformed into boric acid in this process, while the other one serves as the
co-catalyst to stabilize the transition state via hydrogen bonds.
a) b)
Figure 1. a) Plot of icat vs. [buffer base]3/2. The inset shows the structure of
[Cu(meso-L)]2+; b) Transition state structure of O−O bond formation step. Atom colors
are white (hydrogen), gray (carbon), red (oxygen) and golden (copper).
REFERENCES
[1] Wang, D.; Groves, J. T. Proc. Natl. Acad. Sci. U. S. A. 2013, 110, 15579.
P2-20
Advanced lithium-sulfur batteries: The critical role of carbon
Qiang Zhang*, Jia-Qi Huang, Xin-Bing Cheng, Hong-Jie Peng, Lin Zhu,
Ting-Zhou Zhuang, Zhu Yuan, Dai-Wei Wang, Wancheng Zhu, Fei Wei
Beijing Key Laboratory of Green Chemical Reaction Engineering and Technology, Department of Chemical Engineering, Tsinghua University, Beijing 100084, China
ABSTRACT
With the commercial application of graphite anode, lithium-ion batteries (LIBs) are
extensively applied in numerous portable devices such as smartphones and laptops.
However, current LIBs based on conventional intercalation mechanism cannot meet the
requirements for the electronic industry and electric vehicles yet. Therefore, it is
extremely urgent to seek for the systems with high energy density. Among various
promising candidates with high energy densities, lithium-sulfur (Li-S) batteries with a
high theoretical capacity and energy density are highly attractive;1-2 while the
commercial application of Li-S batteries still faces some persistent obstacles, such as
the low electrical conductivity of sulfur and lithium sulfide and the dissolution of
polysulfides. The introduction of nanocarbon materials into the field of Li-S batteries
sheds a light on the efficient utilization of sulfur by improving the conductivity of the
composites and restraining the shuttle of polysulfides. In this presentation, the recent
progress of the carbon/sulfur composite materials, especially carbon nanotube, graphene,
porous carbon and hybrid materials in my research group will be reviewed.3-10 New
insights on the relationship between the structure and the electrochemical performance,
and proposed some prospects on the future development of Li-S batteries.
REFERENCES
[1] Evers, S.; Nazar, L.F. Acc Chem Res. 2013, 46, 1135.
[2] Manthiram,A; Chung,S.H.; Zu,C.X. Adv Mater. 2015, 27, 1980.
[3] Zhao,M.Q.; Zhang,Q.; Huang, J.Q.; et al. Nature Commun. 2014, 5, 3410.
[4] Cheng, X.B.; Huang, J.Q.; Zhang, Q.; et al. Nano Energy. 2014, 4, 65.
[5] Huang,J.Q.; Zhang,Q.; Peng, H.J.;, et al. Energy Environ Sci .2014, 7, 347.
[6] Tang,C.; Zhang,Q.; Zhao,M.Q.; et al. Adv Mater. 2014. 26, 6100.
[7] Zhao,M.Q.; Peng,H.J.; Tian,G.L.; et al. Adv Mater. 2014, 26, 7051
[8] Yuan, Z.; Peng,H.J.; Huang,J.Q.; et al. Adv Funct Mater. 2014, 24, 6105.
[9] Cheng,X.B.; Peng,H.J.; Huang,J.Q.; et al. ACS Nano. 2015, 9, 6373.
[10] Zhu,L.; Peng,H.J.; Liang, J.Y.; et al. Nano Energy. 2015, 11, 745
P2-21
Toward High-Stable Lithium-Sulfur Battery: Permselective Membrane
System as Ion Shield for Polysulfides
Jia-Qi Huang*, Ting-Zhou Zhuang, Hong-Jie Peng, Qiang Zhang*, Fei Wei
Beijing Key Laboratory of Green Chemical Reaction Engineering and Technology, Department of Chemical Engineering, Tsinghua University, Beijing 100084, China
[email protected]; [email protected]
ABSTRACT
Li-S batteries attract great attention due to their high energy density, while the real
applications are still hindered by the rapid capacity degradation. Despite great effort
devoted to solving the polysulfide shuttle between the cathode and anode electrodes, it
remains as a serious challenge to build high-stable lithium sulfur battery, which related
to the diffusion and reaction between polysulfides and the metal lithium anode.
We proposed a strategy of introducing an ion selective membrane to improve the
stability and coulombic efficiency of lithium sulfur battery. Generally, porous polymer
membrane serves as membranes in batteries to avoid the short circuit between anode
and cathode electrodes, which cannot stop the shuttle effect. By the introduction of
permselective functional layer, the polysulfide anions can be confined in the cathode
side, which would favor the cyclic stability and lower self-discharge performance.
We replace the routine membrane with an ion selective membrane, in which the
sulfonate-ended perfluoroalkyl ether groups on the ionic separators are connected by
pores or channels that are around several nanometers in sizes. These -SO3-- groups
coated channels allow ion hopping of positive charge species (Li+) but reject hopping of
negative ions, such as polysulfide anions (Sn2-) in this specific case due to the coulombic
interactions. Consequently, this cation permselective membrane acts as an electrostatic
shield for polysulfide anions, and confines the polysulfides in the cathode side. An
ultra-low decay rate of 0.08% per cycle is achieved within the initial 500 cycles for
membrane developed in this work, which is less than half that of the routine
membranes.
We also proposed a unique lithium-sulfur battery configuration with ultrathin
graphene oxide (GO) membrane for high stability. The oxygen electronegative atoms
modified GO into a polar plane and the carboxyl groups acted as ion hopping sites of
positively charged species (Li+) while rejected the transportation of negatively charged
species (Sn2-) due to the electrostatic interactions. Such electrostatic repulsion and
physical inhibition largely decreased the transference of polysulfides across the GO
membrane in lithium-sulfur system. By the incorporation of permselective GO
membrane, cyclic capacity decay rate is also reduced from 0.49 to 0.23 %/cycle.
Such ion selective membrane is versatile for various electrodes and working
conditions, which is promising for the construction of high performance batteries.
REFERENCES
[1] Huang, J.Q.; Zhang,Q.; Peng, H.J.; et al. Energ Environ Sci. 2014, 7, 347.
[2] Huang,J.Q.; Zhuang,T.Z.; Zhang,Q.; et al. ACS Nano. 2015, 9, 3002.
P2-22
A Dual-Phase Li Metal Anode Containing Polysulfide-Induced SEI and
Nanostructured Graphene Framework for Li-S Batteries
Xin-Bing Cheng, Hong-Jie Peng, Jia-Qi Huang, Rui Zhang,
Chen-Zi Zhao, Qiang Zhang*
Beijing Key Laboratory of Green Chemical Reaction Engineering and Technology, Department of Chemical Engineering, Tsinghua University, Beijing 100084, China
ABSTRACT
Lithium-sulfur (Li-S) battery, with a theoretical energy density of 2600 Wh kg-1, is
a promising platform for high-energy and cost-effective electrochemical energy storage.
However, great challenges such as fast capacity degradation and safety concern prevent
it from widespread application. With the adoption of Li metal as the anode, dendritic
and mossy metal deposited on the negative electrode during repeated cycles leads to
serious safety concerns and low Coulombic efficiency. Herein, we reported a distinctive
structure of graphene framework coated by in-situ formed solid electrolyte interphase
(SEI) with Li deposited in the pores as the anode of Li-S batteries. The graphene anode
demonstated a superior dendrite-inhibition behavior in 70 h lithiation while cell with Cu
foil anode was short-circuited only after 4 h lithiation at 0.5 mA cm-2. The graphene
modified anode with SEI induced by the polysulfide containing electrolyte improved the
Coulombic efficiency to ∼97 % for more than 100 cycles, while the control sample with
Cu foil as the current collector exhibited huge fluctuations in Coulombic efficiency. The
unblocked ion pathways and high electron conductivities of frameworks in the modified
metal anode led to the rapid transfer of Li ions through the SEI and endow the anode
framework with an ion conductivity of 7.81×10-2 mS cm-1, nearly quintuple to that of
the Cu foil anode. Besides, the polarization in the charge-discharge process was halved
to 30 mV. The stable and efficient Li deposition was maintained after 2000 cycles. Our
results indicated that nanoscale interfacial electrode engineering could be a promising
strategy to tackle the intrinsic problems of lithium metal anodes, thus improving the
safety of Li-S cells.
REFERENCES
[1] Cheng,X.B.; Zhang,Q. J Mater Chem A. 2015, 3, 7207.
[2] Cheng,X.B.; Huang,J.Q.; Peng, H.J.; Wei, F.; Zhang, Q. Small 2014, 10, 4257.
[3] Cheng, X.B.; Peng, H.J.; Huang, J.Q.; Zhang, R.; Zhao,C.Z.; Zhang,Q. ACS Nano
2015, 9, 6373.
P2-23
Flexible solid-state supercapacitor based on a metal-organic
framework interwoven by electrochemically-deposited PANI
Lu Wanga, Xiao Fenga, Bo Wanga
a Key Laboratory of Cluster Science, Ministry of Education of China, School of
Chemistry, Beijing Institute of Technology, 5 South Zhongguancun Street, Beijing 100081, P. R. China
ABSTRACT
Supercapacitors (SCs) with high power density and long cycle life have drawn great attentions by virtue of their balanced rate performance and energy density. Among these SCs, flexible solid-state supercapacitors (SSCs) are considered to be promising candidates for electrochemical energy storage towards lightweight, safe, eco-friendly and easy-to-handle devices, since they avoid using liquid electrolyte and can be easily folded or attached to any surfaces. Emerging as a new class of porous materials with exceptional porosities and well-defined pores,[1] metal–organic frameworks (MOFs), which are constructed by joining metal ions with organic links, are widely applied in gas separation, sensor,[2] and Li-ion battery.[3] Quite recently, MOFs have received increasing attention as promising electrode materials in SCs.[4] Yet poor conductivity in most MOFs largely thwarts their capacitance and/or rate performance. In this work, an effective strategy was developed to reduce the bulk electric resistance of MOFs by interweaving MOF crystals with polyaniline (PANI) chains that are electrochemically-deposited on MOFs. Specifically we synthesized cobalt-based MOF crystals (ZIF-67) onto carbon cloth (CC) and further electrically deposited PANI to give a flexible conductive porous electrode (noted as PANI-ZIF-67-CC) without altering the underlying structure of the MOF. A synergistic effect is observed in this approach. The deposited PANI can efficiently improve the conductivity of MOFs and enhance Faradic processes across the interface. Electrochemical studies showed that the PANI-ZIF-67-CC exhibits an extraordinary areal capacitance of 2146 mF cm-2 at 10 mV s-1. And a symmetric flexible solid-state supercapacitor was also assembled and tested. This strategy may shed light on designing new MOF-based supercapacitors and other electrochemical devices.[5] REFERENCES
[1] Furukawa, H.; Cordova, K. E.; O'Keeffe, M.; Yaghi, O. M. Science 2013, 341, 1230444; [2] Guo, Y.; Feng, X.; Han, T.; Wang, S.; Lin, Z.; Dong, Y.; Wang, B. J. Am. Chem. Soc. 2014, 136, 15485. [3] Han, Y.; Qi, P.; Li, S.; Feng, X.; Zhou, J.; Li, H.; Su, S.; Li, X.; Wang, B. Chem. Commun. 2014, 50, 8057. [4] Choi, K. M.; Jeong, H. M.; Park, J. H.; Zhang, Y.-B.; Kang, J. K.; Yaghi, O. M. ACS Nano 2014, 8, 7451. [5] Wang, L.; Feng, X.; Ren, L.; Piao, Q.; Zhong, J.;Wang, Y.; Li, H.; Chen, Y.; Wang, B. J. Am. Chem. Soc. 2015, 137, 4920.
P2-24
How to get a conversion reaction reversible? Lithium storage in metal sulphide
nanodots Yan Yu,a
aDepartment of Materials Science and Engineering,University of Science and Technology of
China,Heifei,230026, China Email:[email protected]
In the context of lithium storage, four modes are well-investigated: single phase storage, two phase storage, interfacial storage and conversion reaction. Conversion reactions have attracted great attention among all these lithium storage modes. The theoretical capacity is very high since more than one electron can be transferred per transition metal ion based on conversion reaction. However, the kinetic problems associated with such reaction are extraordinarily severe, leading to a poor cycling performance. Here we present several examples to show how to make the conversion reaction more reversible. Our solution is to prepare mechanically isolated but electrochemically well connected nanodots.
One of the impressive examples is nanodots of MoS2 embedded in thin carbon nanofibers, which was successful synthesized through electrospinning process with post heat treatment.[1] The dimension of MoS2 is extremely small, the thickness of that is 0.4 nm, indicating the presence of single-layered MoS2.The lateral dimension is quite small as well, only around 4 nm. In this case, the local electroactive mass will be small and they are extremely confined in the thin amorphous carbon nanowires (~50 nm). This point turns out to be quite important for the reversibility and cycling stability of the conversion reaction. Due to such unique morphology, the electrochemical performance in terms of lithium storage is excellent. The capacity maintains 1007 mAh/g after 100 cycles at a current density of 1A/g, and still delivers 661 mAh/g at a high current density of 10A/g. Not only are the lithium storage properties found to be outstanding, but also the storage behaviour of such nanodots is highly exciting from a fundamental point of view, as the differences between the usual storage modes are blurred, such as insertion, conversion and interfacial storage. The confinement of tiny nanodots domains allows for an almost nucleation-free “conversion”, leading to a high capacity and outstanding cycling performance. This will not only lead to higher reversibility but also to lower conversion voltage. The conversion voltage (a realistic equilibrium value is between 0.6 and 1V) is substantially less than the value calculated from bulk thermodynamics (1.5V). Such a shift can be understood by the small size of reaction domains.[1]
Moreover, this concept of extreme reaction confinement can be applied to other conversion electrodes. The other pertinent example is FeS nanodots in porous graphitic carbon nanowires, which are obtained by a combination of electrospinning and biomolecular-assisted hydrothermal method.[2] Usually, the electrospun carbon nanowires will be amorphous even annealed at temperature range between 500-800 °C.
Here, due to the catalytic effect of Fe, partially graphitic and highly porous carbon nanowires were obtained. The materials show surface area of 226 m2/g and pore size distribution in the range of 1-10 nm. Nanodots of FeS with size of 5-10 nm dispersed in such graphitic and porous carbon nanofibers. This morphology shows excellent rate performance, for example, the capacities are in the range of 300-600 mAh/g if current rates are in the range of 0.1C to 10C in the voltage window of 1-3 V, which can be considered as cathode materials for lithium batteries. The energy density is even higher than that of commercial lithium cathode, i.e. LiCoO2. Furthermore, well-defined, flat and symmetric charge-discharge plateaus are quite impressive, which indicates a high reversibility. The total voltage loss in a cycle is less than 0.3V, which is quite small among conversion electrodes. REFERENCES
[1] C. Zhu, X. Mu, P. A. van Aken, Y. Yu and J. Maier, Angewandte Chemie International Edition, 2014, 53, 2152. [2]C. Zhu, Y.-R. Wen, P. A. van Aken, J. Maier, and Y. Yu, Advanced Functional Materials, accepted, http://dx.doi.org/10.1002/adfm.201404468 .
P2-25
Multi-Yolk-Shell CuO@C Octahedra Anodes for High Capacity
Lithium Batteries
Zhong Jin*a, Jie Liu*ab
aSchool of Chemistry and Chemical Engineering, Key Laboratory of Mesoscopic
Chemistry of MOE, Nanjing University, Nanjing 210093 bDepartment of Chemistry, Duke University, Durham, USA
ABSTRACT
Although transition metal oxides have attracted considerable attention for their
high energy density as anode materials of lithium-ion batteries, they suffer from large
volume expansion during lithiation process, which usually causes fast capacity
degradation. Herein, we report a rational design and facile preparation strategy of
copper oxide encapsulated mesoporous carbon multi-yolk-shell octahedra, in which
multiple CuO nanoparticles are well-confined in the compartments of micro-scale
octahedral carbon scaffolds[1]. The advantages of the novel multi-yolk-shell design are
that the 3D carbon scaffolds can buffer the volume change and prevent aggression of
CuO nanoparticles during the charge/discharge cycles, provide pathways for electron
transport and Li+ diffusion, and restrict the thin solid-electrolyte interphase (SEI) layer
to the outer surface of carbon shells. The results demonstrate how the electrochemical
properties of anodes can be significantly improved by the multi-yolk-shell
nanostructures with greatly enhanced structural stability and electrochemical actuation.
Moreover, the micrometer-size CuO@C octahedra reduce the relative quality of SEI,
resulting in high Coulombic efficiency and long cycling stability. In Li-ion cells, the
CuO@C multi-yolk-shell octahedra anodes deliver a highly-reversible capacity of 598
mAh·g-1 at 250 mA·g-1, excellent rate capacity of 365 mAh·g-1 at 3000 mA·g-1 and
exhibit long-term cyclability with a capacity of 512 mAh·g-1 after 300 cycles at 500
mA·g-1.
REFERENCES
[1] Chen, T.; Jin, Z. Liu, J. et al., Nano Energy 2015, in revision.
P2-26
Rational design of a metal–organic framework host for sulfur storage in fast, long-cycle Li–S batteries
Siwu Lia, Xiaotao Fua, Xiao Fenga, and Bo Wanga
aSchool of Chemistry, Beijing Institute of Technology, Beijing, 100081, China
ABSTRACT Unlike an intercalation cathode, which has an intrinsic host structure made of redox metal sites allowing the transport of Li+/e-, sulfur as a conversion cathode requires an additional host to store and immobilize the mobile redox centers, polysulfides. [1]
Metal–organic frameworks (MOFs) as a class of highly porous and well-defined crystalline materials are a promising platform to search for an effective host through rational design. With the appropriate selection of an electrolyte and a cutoff voltage range, sulfur stored in an appropriate MOF host can take advantage of both intercalation (fast and stable) and conversion (high energy density) cathodes. [2-4] We chose a fast cathode with long cycle life based on sulfur and ZIF-8 nanocrystals. With 30 wt% sulfur loading in the electrode, it achieves remarkable discharge capacities of 1055 mAhg-1 (based on sulfur) at 0.1 C and 710 mAhg-1 at 1 C. The decay over 300 cycles at 0.5 C is 0.08% per cycle, prominent in long-cycle Li–S batteries. By comparing with another three distinct MOFs, MIL-53 (Al), NH2-MIL-53 (Al) and HKUST-1, as well as two sets of ZIF-8 with particle sizes in the micrometer range, it reveals that (i) the small particle size of the MOF host is appreciable to achieve a high capacity and (ii) small apertures, associated with functionalities in the open framework that have affinity with the polysulfide anions, can help achieve a stable cycling. We believe that the findings are general and applicable for the rational design of new hosts for sulfur in other porous material families to produce more effective and stable Li–S batteries.[5-6] REFERENCES [1] Ellis, B. L.; Lee, K. T.; Nazar, L. F. Chem. Mater. 2010, 22, 691. [2] Furukawa, H.; Cordova, K. E.; Yaghi, O. M. et al. Science 2013, 341, 974. [3] Demir-Cakan, R.; Morcrette, M.; Tarascon, J.-M. et al. J. Am. Chem. Soc. 2011, 133, 16154. [4] Zheng, J.; Tian, J.; Xiao, J. et al. Nano Lett., 2014, 14, 2345. [5] Zhou, J.; Li, R.; Wang B. et al. Energy Environ. Sci. 2014, 7, 2715. [6] Zhou, J.; Li, H.; Wang B. et al. J. Mater. Chem. A, 2015, 3, 8272.
P2-27
Printed electronics integrated with flexible supercapacitors: new
methodologies for low-cost energy storage
Yang Wanga, Yi-Zhou Zhanga, Wen-Yong Laia, Wei Huanga
a Key Laboratory for Organic Electronics & Information Displays (KLOEID), Institute
of Advanced Materials (IAM), National Jiangsu Syngerstic Innovation Center for Advanced Materials (SICAM), Nanjing University of Posts and Telecommunications
(NUPT), Nanjing, 210023 (China) [email protected]
ABSTRACT
Flexible electronics represents one important aspect of modern electronics. Paper,
due to the low-cost nature and the excellent mechanical properties, has great potential as
the substrate for flexible electronic devices. We are particularly interested in one type of
energy storage devices on paper-flexible supercapacitors (SCs) on paper.[1]
We start with the synthesis of novel SC electrode materials, as an example, porous
hollow Co3O4 was synthesized which show high electrochemical performance as SC
electrode material.[2] The Co3O4 was prepared by the calcination of ZIF-67 ([Co(mim)2;
mim = 2-methylimidazolate]) to exhibit a rhombic dodecahedral morphology as shown
in Fig. 1a-c.
Figure. 1 (a-c) SEM images of the porous hollow Co3O4 rhombic dodecahedral
structure, (d) microscope images of silver electrodes printed onto NC membrane.
Printing methods have the potential to yield useful energy storage devices at a
low-cost which augments the advantages endowed by paper as a substrate. We used
inkjet printing to print conductive materials on paper as a low-cost and large scale
process to fabricate continuous patterns as current collectors and/or electrodes for SCs.
For instance, Fig. 1d shows microscope image of silver electrodes printed onto
nitrocellulose (NC) membrane.[3]
REFERENCES
[1] Zhang, Y.-Z.; Wang, Y.; Cheng, T.; Lai, W.-Y.; Pang, H.; Huang, W. Chem. Soc. Rev. 2015, 44, 5181.
[2] Zhang, Y.-Z.; Wang, Y.; Xie, Y.-L.; Cheng, T.; Lai, W.-Y.; Pang, H.; Huang, W.
Nanoscale 2014, 6, 14354.
[3] Jenkins, G.; Wang, Y.; Xie, Y. L.; Wu, Q.; Huang, W.; Wang, L.; Yang, X. Microfluid. Nanofluid. 2015, 19, 251.
P2-28
Hybrid Materials for Anode of Lithium Ion Batteries (LIBs) Yanglong Hou a,*, Nasir Mahmood a, Xingxing Gu a, Han Yin a, Xiaoxiao Huang a
a Department of Materials Science and Engineering, College of Engineering, Peking University, Beijing 100871 (China)
ABSTRACT
Presently, safe energy storage is one of the most demanding technologies by the
developing society. In this regard, lithium ion batteries (LIBs) and Supercapacitors (SC)
have got tremendous attention due to their high energy and power densities; have been
considered as promising power source for future electric vehicles (EVs). Thus, most of
the present research is focused to develop new electrode materials that can bring the
realization of these devices for EVs. However, structural disintegration, limited access
to redox sites and loss of electrical contact have long been identified as primary reasons
for capacity loss and poor cyclic life of these materials. Although nanotechnology plays
critical role by developing nanostructures but simple reduction in size introduce new
fundamental issues like side reactions and thermally less stable. Thus, a careful design
that can inhibit the side reaction by surface protection, make all redox sites accessible
by increasing the intrinsic conductivity of the active materials, maintain a continues
network for ionic and electronic flow and keeps the structural integrity, resulting
improved performance and excellent capacity retention with long cyclic life to meet the
requirements set by USABC for electrode materials to use them in EVs. Here, we have
developed different hybrid structures of metal oxides, nitrides, sulfides, hydroxides and
metal alloys with doped graphene to control above mentioned problems and to achieve
the goals set by USABC. All these composites possess extraordinary performances as
electrodes of LIBs and SC with long cyclic stability and excellent rate capability. The
high performance of the composites based on the synergistic effect of several
components in the nanodesign. These strategies to combine the different property
enhancing factors in one composite with engineered structures will bring the realization
of these devices in road market.
REFERENCES
[1] Mahmood, N.; Zhu, J.; Rehman, S.; Li, Q. and Hou, Y. Nano Energy 2015, 15, 755.
[2] Mahmood, N.; Tahirb, M.; Mahmood, A.; Zhu, J.; Cao, C. and Hou, Y., Nano Energy 2015, 11, 267.
[3] Mahmood, N. and Hou, Y., Adv. Sci. 2014, 1, 1400012.
[4] Li, Q.; Mahmood, N.; Zhu, J.; Hou, Y. and Sun S., Nano Today 2014, 9, 668.
[5] Zhang, C.; Hao, R.; Liao H. and Hou, Y., Nano Energy 2013, 2, 88.
[6] Zhang, C.; Mahmood, N.; Yin, H.; Liu, F. and Hou, Y., 2013, Adv. Mater. 25, 4932.
[7] Mahmood, N.; Zhang, C.; Jiang, J.; Liu, F.; Hou, Y., Chem. Eur. J. 2013, 19, 5183.
[8] Mahmood, N.; Zhang, C. and Hou, Y., Small 2013, 9, 1321.
[9] Mahmood, N.; Zhang, C.; Liu, F.; Jinghan, Z. and Hou, Y., ACS Nano 2013, 11,
10307.
[10] Mahmood, N.; Zhang, C.; Yin, H. and Hou, Y., J. Mater. Chem. A 2014, 2, 15.
[11] Yin, H.; Zhang, C.; Liu F. and Hou Y., Adv. Funct. Mater. 2014, 24, 2930.
P2-29
-1.0 -0.8 -0.6 -0.4 -0.2 0.0
-6
-4
-2
0
2
4
6
8
10
Cu
rre
nt
(mA
)
Potential (V)
HCF
PHCF1
PHCF2
Porous heteroatoms-enriched carbon fibers based on PVP/MF as the
electrode material for Supercapacitors Chuanli Qin, Ting Sun, Weijie Wang, Chenlong Wang, Yonghe Wang
School of Chemistry and Materials Science, Heilongjiang University,Harbin 150080 [email protected]
ABSTRACT In order to develop porous heteroatoms-enriched carbon fibers(PHCF) with high
specific surface area and hereroatom concentration as electrode materials for
supercapacitors, we prepared the mixture solution of melamine formaldehyde resin (MF)
and polyvinyl alcohol (PVA) with ammonium chloride(NH4Cl) or polyethylene glycol
(PEG) as the pore-forming agent by the simple electrospinning and subsequent thermal
treatment process.The results show that samples consist of overlapped fibers and
possess 3D network and hierarchical porous structure. A lot of mesopores are formed in
PHCF, providing stable ionic transfer channels, and resulting in enhanced
electrochemical performances. PHCF owns higher N and O hereroatom concentration
than HCF, improving the specific capacitance by pseudocapacitive interactions between
electrolyte ions and heteroatoms. CV measurements show that PHCF2 has the highest
specific capacitance(190.9F/g at 1mV/s) due to its highest specific surface area,
mesopore volume and hereroatom concentration(3.65 at.% N and 15.98 at.% O).
PHCF2 might be a promising candidate for the electrode material for supercapacitors.
Figure.1 SEM images of (a)HCF without NH4Cl or PEG, (b)PHCF1 prepared with 5
wt.% NH4Cl, (c)PHCF2 prepared with 15 wt.% PEG. The inset shows the
cross-sectional
Figure.2 N2 adsorption/desorption isotherms Figure.3 Cyclic voltammogram curves
and pore size distributions of samples samples at 1mV/s
Table 1 Data from N2 adsorption/desorption isotherms
Samples SBET(m2/g) Smic(m2/g) Smes(m2/g) Vtot(cm3/g) Vmic(cm3/g) Vmes(cm3/g)
HCF 278.6 239.1 24.7 0.1621 0.1237 0.0279
PHCF1 141.8 117.7 72.3 0.1411 0.0609 0.1055
PHCF2 591.0 95.2 310.4 0.4007 0.0624 0.2568
REFERENCES
[1] Qian, W. J.; Sun, F. X.; Xu, Y. H.; Qiu, L. H.; Liu, C. H.; Wang S. D.; Yan, F. Energy Environ. Sci. 2014, 7, 379
0.0 0.2 0.4 0.6 0.8 1.0
0
50
100
150
200
250
300
350
400
Qua
ntity
Ads
orbe
d (c
m3 /
g S
TP
)
Relative Pressure (P/Po)
PHCF1
HCF
PHCF2
0 2 4 6 8 101214161820
0.00
0.04
0.08
0.12
0.16
0.20
dV/d
R (
cm3 /n
m/g
)
Pore width (nm)
HCF
PHCF1
PHCF2
P2-30
The excellent rate capability of synthetic graphite with abundant
hollow carbon nanostructures for lithium storage
Canliang Maa, *, Yun Zhaoa
a Key Laboratory of Materials for Energy Conversion and Storage of Shanxi Province,
Institute of Molecular Science, Shanxi University, Taiyuan, 030006, China
ABSTRACT
High lithium storage capacities have been achieved over some carbon materials through lithium storage in micropores, hollow carbon cages and hollow carbon nanostructures (HCNs). [1-3] In the previous work, we fabricated HPS NiP-NG (S2) using 25 wt.% NiP( nickel content is 9.44%) as binder. [3] For evaluating the role of HCNs, we prepared artificial graphite from the above mentioned NiP and noted as HCl(NiP-G2700) (S1). The representative microstructure of the S1 is presented in Fig. 1. Abundant HCNs with the average diameter of 25 nm are found in S1. Fig.2 shows the rate capability of samples at the current density from 0.1 to 1Ag-1, and back to 0.1Ag-1. The performance improvements are significant, S2 receives 359 mAhg-1 at 0.1Ag-1, which is much higher than that of NG, meanwhile, S1 with more abundant HCNs than S2 gets reversible capacity as high as 451 mAhg-1. When the current density increase to1Ag-1, S1 still obtained 284 mAhg-1, showing an excellent rate capability. As a whole, the lithium storage capacity and rate capability of S1 is much higher than that of S2, which might be due to the quantity of HCNs.[3] The curves of galvanostatic discharge –charge at different current densities reveal the plat of S1 are longer than S2(Fig.3), which makes this point that there are more lithium store in HCNs a little more visually.
REFERENCES
[1] Zhou,G., Wang, D.W., Shan, X., Li, N., Li, F., Cheng, H.M. J. Mater. Chem. 2012, 22, 11252. [2] Han, F.D., Yao, B, Bai, Y.J. J. Phys. Chem. C 2011,115,8923,. [3] Ma, C., Zhao, Y., Li, J., Song, Y., Shi, J., Guo, Q., Liu, L. Carbon 64, 553
P2-31
1st International Symposium on Energy Chemistry & Materials, Oct. 29‒31 2015, Fudan University, Shanghai, China
Three-demensional Hierarchical FeOOH/TiO2/ZnO Nanostructural
Photoanode for Photoelectrochemical Water Splitting
Zhenhu Li, Shuangyi Liu
Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing 400714, P. R. China.
E-mail: [email protected]; [email protected]
ABSTRACT
Sunlight-driven photoelectrochemical (PEC) water splitting into hydrogen and
oxygen presents a promising way to utilize renewable solar energy effectively and has
been explored by lots of researchers.[1]
We designed and fabricated a novel
ZnO/TiO2/FeOOH hierarchical nanostructure by a low temperature chemical bath
deposition method. The integrated three-dimensional (3D) nanostructure consists of
one-dimensional (1D) ZnO/TiO2 core-shell nanowire arrays and two-dimensional (2D)
interconnected FeOOH nanosheets. With applying such hierarchical nanostructure as a
photoanode of photoelectrochemical water reaction, higher photostability and
photocurrent density are gained comparing with that of reported ZnO based
nanostructures. It is concluded that the giant enhancement of the properties is because,
in process of photoelectrochemical reaction, electron-hole separation and transfer are
enhanced efficiently through the ZnO/TiO2 heterojunction, and in the meanwhile,
terminal interconnected FeOOH nanosheets play both roles of surface catalyst and
protection effectively to accelerate water splitting reaction and enhance photostability.[2]
Based on such environmental friendly hierarchical nanostructure, photoelectrochemical
water splitting and the other similar reactions could be performed effectively and
economically.
REFERENCES
[1] Fan, G.; Li, F.; Evans, D. G.; Duan, X. Chem. Soc. Rev., 2014, 43, 7040.
[2] Kim, T. W.; Choi, K.-S. Science, 2014, 343, 990.
P2-32
Covalent cobalt porphyrin framework on multiwalled carbon
nanotubes for efficient water oxidation at low overpotential
Hongxing Jia, Zijun Sun, Daochuan Jiang, Pingwu Du*
Key Laboratory of Materials for Energy Conversion, Chinese Academy of Sciences, Department of Materials Science and Engineering, iChEM (Collaborative Innovation Center of Chemistry for Energy Materials), University of Science and Technology of China (USTC), 96 Jinzhai Road, Hefei, Anhui Province 230026, People’s Republic of
China. * [email protected]
ABSTRACT
A noble-metal-free, efficient, and robust catalyst made of earth-abundant elements
for water oxidation is vital to achieve practical water splitting for future clean energy
production. Our previous study showed that cobalt porphyrin can be used as efficient
water oxidation catalyst. [1] Herein, we report the synthesis of multi-layer covalent
cobalt porphyrin framework on multiwalled carbon nanotubes ((CoP)n-MWCNTs) to
produce a highly active electrocatalyst for water oxidation. [2] A linear sweep
voltammetry curve showed that a catalytic current density of 1.0 mA/cm2 can be
achieved under a potential of only 1.52 V (vs. RHE, corresponding to an overpotential
of only 0.29 mV) in alkaline solution at pH 13.6. In addition, the chronopotentiometry
data suggest that (CoP)n-MWCNTs catalyst has good durability for water oxidation. A
Tafel slope of 60.8 mV per decade was obtained by bulk electrolysis measurement and
the Faradaic efficiency of oxygen production was >86%. All the results show that
(CoP)n-MWCNTs is among the best molecular catalyst for water oxidation.
Figure 1. (CoP)n-MWCNTs for water oxidation
REFERENCES
[1] Han, A.; Jia, H.; Ma, H.; Ye, S.; Du. P. Phys. Chem. Chem. Phys. 2014, 16, 11209.
[2] Jia, H.; Sun, Z.; Jiang, D.; Du. P. Chem. Mater. 2015, 27, 4586.
P2-33
Superwetting Electrodes for Gas-involved Electrochemical Catalytic
Reactions
Xiaoming Sun1* and Zhiyi Lu1
1 State Key Laboratory of Chemical Resource Engineering, P.O. Box 98, Beijing University of Chemical Technology, Beijing, 100029, China
Abstract:
Electrochemical catalytic reactions are now playing an important role in
current chemical industry, among them the electrochemical gas evolution and
consunption reactions are the most attractive topics. Here we review some recent
progresses in our laboratory related to the hydrothermal synthesis of carbon materials,
metal oxides/hydroxides and metal chalcogenides nanoarrays, whose structures are
designed aiming to the application of electrochemical catalysts. After careful
measurements, we found that constructing the nanoarray architecture could bring
about a boost improvement of the catalyst, which was attributed to the tight
connection to the substrate and accelerating the electron/electrolyte penetration.[1-2]
More importantly, the surface morphology can reduce/enhance the adhesion to the gas
bubbles and thus promote gas releasing/diffusion processes, which were demonstrated
by a variety of gas-involved reactions (e.g. hydrogen evolution reaction, oxygen
evolution reaction, nitrogen evolution reaction and oxygen reduction reaction).[3-4]
These developments clearly demonstrate the benefits of nano-array architecture and
guide the optimal structural design for future energy related process.
References:
[1] Liu,X.; Liu,J.; Sun,S.; et al. Chem. Mater. 2014, 26, 1889
[2] Lu,Z.; Sun,X.; et al. Chem. Commun. 2014, 50, 6479
[3] Lu,Z,; Sun,X.; Jiang,L.; et al. Adv. Mater. 2014, 26, 2683
[4] Lu,Z,; Sun,X.; Jiang,L.; et al. Adv. Mater. 2015, 27, 2361
P2-34
3D WS2 Nanosheet-Networks as
H2O2 Produced for Cell Signaling
Jing Tang a, Yingzhou Quana, Gengfeng Zhenga*
a Laboratory of Advanced Materials, Department of Chemistry, Collaborative
Innovation Center of Chemistry for Energy Materials, Fudan University, Shanghai 200433, P. R. China
ABSTRACT
Hydrogen peroxide (H2O2) is gradually becoming a newly accepted messenger in cellular signal transduction.[1] However, the potential for elucidating its manifold roles in complex biological environments is limited, which is lack of effective methods for probing this reactive oxygen metabolite in living systems with specificity. Herein, a general strategy to fabricate three-dimensional (3D) WS2 nanosheet networks with flower-like morphology based on a facile chemical vapour deposition (CVD) approach is proposed. The semiconducting 2H-WS2 into nanosheets result in the excellent electrical transport and proliferation of catalytically active sites. Owing to the unique features of 3D WS2, such as high permeability to biosubstrates and rapid electron transfer with ehanced interlayer coupling of electron orbitals, the 3D WS2-based nano-bio-interface demonstrate high selectivity for H2O2 and are capable of visualizing endogenous H2O2 produced in living cells by growth factor stimulation, including the first direct sensing of peroxide produced for brain cell signaling.[2] The combined features of reactive oxygen species selectivity, sensitivity to signaling levels of H2O2, and live-cell compatibility presage many new opportunities for 3D WS2 for exploring the physiological roles of H2O2 in living systems. It indicates excellent bioprobing performance with a wide linear range and high sensitivity, and rapid response time (∼3 s). The activity of neuronal cells has been enhanced by promoting the interaction between subcellular structures and 3D topographic features, showing higher density and greater cell polarization. Furthermore, the 3D H2O2 bio-interface with excellent electrocatalytic activity, surface-rich microstructure and maxmized exposure of active sites leads to a wide detective range (1 nM to 400 μM), and an ultra sensitive detection limit (as low as 0.02 nM) towards H2O2., the best performance based on biocatalyisis of transition metal dichalcogenides (TMDs). Computational analyses further testify that the enhanced sensitivity of probing H2O2 is associate with the spontaneous adsorption on WS2 nanosheet. The trace amount of H2O2 released from Raw 264.7 cells and neurons is also successfully recorded, which achieves the sensitive and real-time quantitative probing of H2O2 in biological environment. REFERENCES
[1] Dickinson, B. C.; Chang, C. J. Nat. Chem. Biol. 2011, 7, 504. [2] Duan, X.; Wang, C.; Shaw, J. C.; Cheng, R.; Chen, Y.; Li, H.; Wu, X.; Tang, Y.; Zhang, Q.; Pan, A.; Jiang, J.; Yu, R.; Huang, Y.; Duan, X. Nat. Nano 2014, 9, 1024.
P2-35
High-Performance Hydrogen Generation from Liquid Chemical
Hydrogen Storage Materials over Supported Metal Nanocatalysts Jia Cheng, Xiaojun Gu,* Lingling Guo, Kai Kang, Tianshu Wang, Haiquan Su*
Inner Mongolia Key Laboratory of Coal Chemistry, School of Chemistry and Chemical Engineering, Inner Mongolia University, Hohhot 010021, China
[email protected], [email protected]
ABSTRACT
The search for effective hydrogen storage materials and methods for hydrogen
generation in safe and efficient ways remains one of the most challenging barriers in the
implementation of a fuel-cell-based hydrogen economy.[1] Due to the high hydrogen
content of 19.6 wt%, ammonia borane (NH3BH3) is currently a favourable candidate for
chemical hydrogen storage applications.[2] However, how to remarkably enhance the
activity of catalysts in hydrolysis of NH3BH3 still remains a challenge. Herein, we
reported a series of AuM (M = Co, Ni) nanoparticles (NPs) immobilized by porous
functionalized carbon materials, namely, amine-functional carbon nanotube (CNT),
N-doped active carbon (NXC) and graphite carbon nitride (C3N4), using three different
reduction ways towards mixed metal ions AuCl4 and M2+.[3] All the catalysts exhibited
high dispersion and small size of bimetallic NPs; however, they exhibited remarkably
different catalytic activities featuring total turnover frequency (TOF) values from 6.4 to
42.1 molH2molcat-1min-1 (Figure 1). Among all the catalysts, the NXC-immobilized
AuCo NPs through in situ synthesis exhibited the highest activity with a total TOF value
of 42.1 molH2molcat-1min-1. This remarkably enhanced activity may be attributed to the
synergistic effect of N-doped carbon support and AuCo NPs and the resulting highly
efficient activation of N-B bond in NH3BH3. Through designing and selecting porous
functionalized materials as supports to tune the interactions between supports and active
metal NPs with different structures, it is possible to design high-performance
nanocatalysts that are important for sustainable energy production and chemical synthesis applications.
Figure 1. Plots of time versus volume of H2 generated from aqueous NH3BH3 over (a)
Au-Co/NXC, (b) Au-Co/C3N4 and (c) Au-Co/CNT at room temperature.
REFERENCES
[1] Edwards, P. P.; Kuznetsov, V. L.; David W. I.; Brandon, N. P. Energy Policy 2008, 36,
4356.
[2] Zhu Q.-L.; Xu, Q. Energy Environ. Sci. 2015, 8, 478.
[3] Kang, K.; Cu, X.; Guo, L.; Liu, P.; Sheng, X.; Wu, Y.; Cheng, J.; Su, H. Int. J. Hydrogen Energy, 2015, 40, 12315.
P2-36
1st International Symposium on Energy Chemistry & Materials, Oct. 29‒31 2015, Fudan University, Shanghai, China
Diamine-Coupled Polyaniline Fiber/Graphene Hybrids for
Supercapacitors with High-Rate Performance
Xin Xia, Dongqing Wub, Ruili Liuc
aDepartment of Chemical Engineering, School of Environment and Chemical
Engineering, Shanghai University, Shanghai 200444, China. bSchool of Chemistry and Chemical Engineering, Shanghai Jiao Tong University,
Shanghai 200240, China. cState Key Laboratory of Advanced Optical Communication Systems and Networks, Department of Electronic Engineering, Shanghai Jiao Tong University, Shanghai
200240, China. E-mail: [email protected]
ABSTRACT
Due to the high charge–discharge rate as well as long cycling life, supercapacitors
(SCs) are widely regarded as the next generation power sources for electrical vehicles, back-up supplies and load-levelling.1 To meet the demands of high performance SCs, different kinds of electrode materials has been developed in the last few years. Among these materials, porous carbonaceous materials, featuring long cycle life and good mechanical properties, have been applied in SCs to store energy through the electric double-layer capacitor mechanism (EDLC). In contrast, pseudocapacitance materials (e.g., metal oxides and conducting polymers) can serve as the alternative electrode materials in SCs via a so-called Faradic mechanism.
Polyaniline (PANI) is one of the most appealing candidates for SCs among
pseudocapacitance materials, owing to its unique conducting mechanism and large specific capacitance (>1000 F g-1).2 To improve the cycling stability of PANI, the composites of graphene and polyaniline were prepared in our work. By introducing diamines as additives to couple PANI fibers and graphene substrates, the hybrids keep 84.4% of its initial capacitance after 10000 cycles. What’s more, the electrodes also exhibit remarkable performance with high specific capacitances of 664 F g-1 at the scan rate 5 mV s-1 in the two-electrode systems. Meanwhile, the retention of the capacitance is about 90% at a high rate of 20A g-1. Composites also reach up to the highest energy density of 92.15Wh kg-1 as well as the highest power density of about 182.28 kW kg-1, when the energy density (50.63 Wh kg-1) is up to the level of the battery. REFERENCES
[1] G. Wang, L. Zhang and J. Zhang, Chem. Soc. Rev. 2012, 41, 797-828. [2] Y. Meng, K. Wang, Y. Zhang and Z. Wei, Adv. Mater. 2013, 25, 6985-6990.
P2-37
1st
International Symposium on Energy Chemistry & Materials, Oct. 29‒31 2015, Fudan University, Shanghai, China
3D Micro-Fabrication of Advanced Li-ion Batteries by Electrochemical Methods
Huigang Zhang1*
, Xindi Yu2, Paul V Braun
2
1.Department of Energy Engineering, College of Engineering and Applied Sciences, Nanjing University, 210093, China.
2.Department of Material Sciences and Engineering, University of Illinois at Urbana-Champaign, 61801, USA
*Email:[email protected], Tel.+86-25-83592805
ABSTRACT
Lithium ion (Li-ion) battery cathodes are usually poor electronic conductor. In a
traditional Li-ion battery, conductive agents are added to decrease the impedance. High
impedance leads to non-uniform charge/discharge at high C-rates and rapid material
degradation. To decrease the impedance, high electron and ion pathways have been
fabricated in the cathode laminates. Adding extra conductive agents could only improve
electronic conduction. Li-ion transport is related to the liquid electrolyte distribution
inside cathodes. In this presentation, we demonstrate a well-designed bi-continuous 3D
scaffolded electrode structures. We fabricated a highly porous nickel inverse opal
(Figure 1a,c) by using a polystyrene sphere opal template. The windows size of Ni
inverse opal is enlarged by an electropolishing route. After electrodepositing active
materials (NiOOH or MnO2 Figure 1b,d), the 3D scaffold electrode was tested at
ultrafast C-rates.
Figure 1. Bicontinuous electrode microstructure.SEM images of a bicontinuous three-dimensional
electrode during each step of preparation.a,Nickel inverse opal after electropolishing (1.8mm
colloidal particle template).b, Cross-section of NiOOH/nickel composite cathode. c, Nickel inverse
opal after electropolishing (466 nm colloidal particle template). d, MnO2/nickel composite cathode.
In conclusion, we make full use of 3D scaffolded electrode structures for rapid
electron and ion transport and demonstrate unique or excellent electrochemical
properties.[1-4]
The capability of manipulating 3D structures on micro- and nano- scales
are pushed forward by the newly developed electrochemical techniques.
REFERENCES
[1]. Yu, X; Zhang, H.; Oliverio, J.K.; Braun, P.V. Nano Lett. 2009, 9, 4424.
[2]. Zhang, H.; Braun, P.V. Nature Nanotechnol. 2011, 6, 277.
[3]. Zhang, H.; Braun, P.V. Nano Lett. 2012, 12, 2778.
[4]. Pikul, J.H.; Zhang, H.; Cho, J.; Braun, P.V.; King W. Nature Commun. 2013, 4, 1732.
a
b d
c
P2-38
Enhancing Electrocatalytic Oxygen Evolution Activity of Li2Co2O4 by
Doping Fe or Ni
Xiao Lin, a Hengjie Liu, a Jing Zhou, a Linjuan Zhang, a Hongliang Bao, a Shuo Zhang,
a,b Sanzhao Song, a,b Jian-Qiang Wanga,b*
a Key Laboratory of Interfacial Physics and Technology and bShanghai Synchrotron Radiation Facility Shanghai Institute of Applied Physics, Chinese Academy of Sciences,
Jialuo Road 2019, Shanghai 201800, P. R. China *E-mail: [email protected]
ABSTRACT
Oxygen evolution reaction is a key step in water splitting, and has been recognized as a bottleneck that significantly limits the overall efficiency of water splitting. Among all of the metal oxides, the Li2Co2O4 have shown a high efficient catalytic activity [1]. Now, we demonstrate that the oxygen evolution activity of Li2Co2O4 can be further enhanced by substituting cobalt with Fe or Ni. Using a facile sol-gel method, pure Fe and Ni-substituted nanoparticles have been successfully synthesized, and carefully examined by PXRD (Fig1a). The electronic structure of Li2Co2O4 was investigated X-ray absorption spectra (XAS) and show the change of different metal center (Fig1b). The OER activities of as-made nanoparticles have been investigated, all of the Fe, Ni-doped Li2Co2O4 catalysts exhibited some degree of enhancement of OER activity. It’s worth mentioning that the Fe-doped Li2Co2O4 manifests the most dramatically enhanced OER catalytic activity (Fig1c) as a result of an unusual synergistic effect [2].
Fig. 1 XRD and XAS patterns and OER performances of the electrocatalysts. (a) Powder XRD patterns of Li2Co2O4, Li2Co1.8Ni0.2O4, Li2Co1.8Fe0.2O4, the inset reveals the peak shift. (b) Co L-edge XAS spectra of Li2Co2O4 (c) Linear sweep voltammograms of Li2Co2O4, Li2Co1.8Ni0.2O4, Li2Co1.8Fe0.2O4 and IrO2 at a scan rate of 5mVs-1 at 1600 r.p.m. in 0.1M KOH.
REFERENCES
[1] Maiyalagan, T.; Jarvis, K.A.; Therese, S.; Ferreira1, P.J.; Manthiram, A. Nat. Commun. 2014, 5, 3949. [2] Xiao, C.; Lu, X.; Zhao, C. Chem. Commun. 2014, 50, 10122.
P2-39
Synthesis of graphene & Ta2O5 as highly Efficient Cathode Catalyst for Rechargeable Lithium-Oxygen Batteries
Luo Liquna , Huang Kekea , Feng Shouhuaa*
a States of Inorganic Synthesis and Preparative Chemistry ,
College of Chemistry, Jilin University, 130012 Changchun, P. R. China
E-mail: [email protected]
ABSTRACT
In order to deal with the problem of the energy shortage, sodium ion batteries, lithium ion batteries and lithium sulfur batteries have been vigorously developed and researched. The lithium air batteries, in particular, due to its high theoretical specific capacity which once again raised a hot wave of science. And still, no tantalum related compounds are applied to the cathode material of lithium air batteries in which our work has great scientific value.
We synthesized a nanocomposite of graphene @ Ta2O5
[1], which owns high dispersion and catalytic activity for Li-air batteries. Battery test shows that the initial discharge specific capacity can be as high as 4652 mAh/g at current density of 100 mA/g. Moreover, the time of discharging is no less than 48 hours, which means it will be a new generation of cathode catalyst for lithium air batteries.
Figure1.TEM image of GO@Ta2O5 Figure2.Initial charge-discharge curves of Li-O2 batteries with GO@Ta2O5 electrodes at a current density of 100 mA/g.
REFERENCES [1] Cherevan A S, Gebhardt P, Shearer C J, et al. [J]. Energy & Environmental Science, 2014, 7(2): 791-796. [2] Cheng F, Chen J. [J]. Chemical Society Reviews, 2012, 41(6): 2172-2192.
P2-40
Facile synthesis of monodisperse V2O5 hollow nanospheres with
enhanced electrochemical performance
Zhang Xianfaa, Xu Yingminga, Cheng Xiaolia, Huo Lihuaa
aKey Laboratory of Functional Inorganic Material Chemistry, Ministry of Education, School of Chemistry and Materials Science, Heilongjiang University, Harbin 150080,
PR China [email protected]
ABSTRACT
Vanadium pentoxide (V2O5) has been extensively studied as a high capacity cathode material for LIBs because of its essential advantages of low cost, easy synthesis, high safety, high specific capacity and energy density[1]. However, the poor cycle performance of the V2O5 material hinders its practical application as a cathode material[2,3]. It is envisaged that the introduction of a hierarchical structure is an effective way to enhance the electrochemical performance of V2O5 materials. Herein, a facile and template-free solvothermal method has been developed to synthesize monodisperse V2O5 hollow spheres. The size of hollow nanospheres are in a range of 300-500 nm with shell thickness of 20-30 nm. The hollow nanosphere precursors gradually formed from solid spheres, to core-shell structures and to hollow spheres. Importantly, the V2O5 hierarchical architecture exhibits an excellent electrochemical performance. At the rate of 0.2 C, these V2O5 flowers deliver a high specific capacity of 285 mA h g-1 in the first discharge. Meanwhile, even at a high rate of 2 C, they also exhibit a specific capacity of 200 mA h g-1 and enhanced cycle performance.
REFERENCES
[1] Pan, A. Q.; Zhu, T.; Wu, H. B.; Lou, X. W. Chem. Eur. J. 2013, 19, 494. [2] Pan, A. Q.; Wu, H. B. ;Zhang, L.; Lou, X. W. Energy Environ. Sci., 2013, 6, 1476. [3] Zhang, X. F.; Wu, M. Z.; Gao, S.; Xu, Y. M.; Cheng, X. L.; Zhao, H.; Huo, L. H. Mater. Res. Bull. 2014, 60, 659.
P2-41
3D hierarchical porous praphene with excellent rate and cycling
performances as anode for Li-ion batteries
Jing Donga, Canliang Maa, HuiLi Chena*,Yun Zhaoa
a Key Laboratory of Materials for Energy Conversion and Storage of Shanxi Province,
Institute of Molecular Science, Shanxi University, Taiyuan, 030006, China
[email protected] ABSTRACT
Owing to its ultra-large specific surface area, rapid diffusion ability for lithium ion,
three dimensional (3D) porous graphene has attracted great attentions of researchers.[1]
Herein, we designed and synthesized a novel 3D hierarchical porous graphene (3D-HPG)
based on a reduced graphite oxide (G250) by vacuum-assisted synthesis[3] with
ferrocene as a pore generator[2] according to the process as shown in Fig.1. Due to the
larger specific surface area and richer hierarchical pores of 3D-HPG than graphene (Fig.
2), lithium ions could transfer more quickly through graphene nanosheets, therefore, a
great rate capability is obtained. Fig. 3 shows a reversible capacity of 160 mAhg-1 at 6.4
Ag-1 with a capacity retention rate of 35.6 % based on the reversible capacity at 0.1 Ag-1.
Meanwhile, it demonstrates an excellent cycling performance when it goes through 200
cycles after a routine rate test. It achieves a reversible capacity of 690 and 948 mAhg-1
at 400 and 100 mAg-1, respectively, which is much more than the initial reversible
capacity at the same current density at the first stage. This 3D-HPG could be a
promising substrate material for advanced composite anode owing to its excellent rate
and cycling performances as well as the facile and non-solvent preparation.
REFERENCES
[1] Zhang, J.; Guo, B.; Yang, Y.; Shen, W.; Wang, Y.; Zhou, X.; Guo, S. Carbon 2015, 84, 469. [2] Wang, J.; Gao,M.; Pan, H.; Liu, Y; Zhang, Z.; Li, J.; Guo, Z. J. Mater. Chem. A. 2015, 3, 14178. [3] Zhang, H. B.; Wang, J. W.; Yan, Q.; Zheng, W. G.; Chen, C.; Yu, Z. Z. J. Mater. Chem. 2011, 21, 5392.
Fig.3 Cycling performance and coulombic
efficiency at stepwise increased current rate
of 3D-HPG
Fig.1 Illustration for the
preparation of 3D-HPG
P2-42
High electrocatalytic activity for borohydride oxidation on palladium
nanocubes enclosed by {200} facets
Haiying Qina, Kaijian Chena, Jiabin Liub
aCollege of Materials and Environmental Engineering, Hangzhou Dianzi University, Hangzhou 310018, China
bSchool of Materials Science and Engineering, Zhejiang University, Hangzhou 310027, China
ABSTRACT
Pd nanocubes enclosed by {200} facets are synthesized and used as an anode
catalyst in direct borohydride fuel cell (DBFC) to study the electrocatalytic activity of
Pd towards borohydride oxidation reaction (BOR) by modifying its surface atomic
structure. A 7e reaction towards BOR is implemented on Pd nanocubes with a
borohydride concentration as high as 3.26 M. The cell using Pd nanocubes as anode
catalyst exhibits an obvious higher power density than the cell using commercial Pd/C,
and maintained 99% of its voltage after 50 h stability test. It suggests that the Pd
nanocubes could be a promising anode catalyst for the DBFC application.
P2-43
Oxygen Selective Membrane Based on MOFs for Lithium Air Batteries
L.J. Cao, F.C. Lv, Y. Liu, W.X. Wang, Y.F. Huo, Z.G. Lu* Department of Materials Science & Engineering, South University of Science and
Technology of China, Shenzhen, Guangdong, China.
ABSTRACT
One of the most critical issues for practical application of Li-air batteries was the contamination of moisture and CO2 from the air. Here we report a high performance O2 selective mixed matrix membrane based on the metal organic framework (MOF) nanocrystallines of CAU-1-NH2@PDA (CAU = Christian-Albrechts-University) and the polymer of polymethylmethacrylate (PMMA) (Fig. 1). In this composite membrane, the functional group –NH2 in the MOF, –OH in the polydopamine molecule, and the –C=O in the PMMA would preferably interact with CO2 molecule. Also, the intrinsic hydrophobic behaviour of the PMMA polymer can favourably prevent the intrusion of moisture (Fig. 1). These two favourable effects guaranteed the Li-air cell working very stable under ambient atmosphere with very high relative humid
(30%) by repelling CO2 and moisture from the air.
Figure 1. The schematic illustration of the MMM based on CAU-1-NH2@PDA (PDA = polydopamine) and PMMA polymer for rebelling H2O and CO2 molecules. The Framework of CAU-1-NH2 viewed along c axis (f) and symbol: Al, pink; O, red; C, gray; H, blue.
REFERENCES
[1] Cao, L.J.; Lv, F.C.; Liu, Y.; Wang, W.X.; Huo, Y.F.; Fu, X.Z.; Sun, R.; Lu, Z.G. Chem. Commun. 2015, 51, 4364; [2] Liu, Y.; Cao, L.J.; Cao, C.W.; Wang, M.; Leung, K.L.; Zeng, S.S.; Hung, T.F.; Chung, C.Y.; Lu, Z.G. Chem. Commun. 2014, 50, 14635. [3] Cao, L.J.; Tao, K.; Huang, A.; Kong, C.; Chen, L. Chem. Commun. 2013, 49, 8513.
P2-44
Cu-Based Alloy Nanocatalysts for Efficient Oxygen Reduction
Reaction
Yaocong Luo, Yifeng Huo, Sisi Wu, Lihua Zhang, Yi Wan, Lujie Cao and Zhouguang
Lu*
Department of Material Science and Engineering, South University of Science and Technology of China, Shenzhen, Guangdong Province, P. R. China
ABSTRACT
Pt and Pt-base alloys may be still the most effective catalysts in oxygen reduction
reaction (ORR). [1] However, their high costs restrain the development of its applications
in industry. Therefore, it is highly attractive and urgent to explore novel catalyst replacing
the noble metal in ORR. Here we report a Cu-based bi-metal alloy nanoparticle derived
from a Cu based complex [2] with a high surface area (1500- 2000 m2/g). Through the
postsynthetic approach, we first prepared Mn, Fe, and Co exchanged Cu-BTC. [3] Then
the obtained samples were calcinated in the Ar gas at 500 C for 5 hours. The prepared bi-
metal nanoparticles were confirmed by X-ray power diffraction (XRD), Transmission
Electron Microscopy (TEM), Energy Dispersive Xray Spectrom (EDX). At last, the ORR
behavior of the bi-metal (Cu-Mn, Cu-Fe and Cu-Co) alloy nanoparticles was evaluated
by the rotating disk electrode (RDE). The ORR activity of bi-metal alloy nanoparticles is
excellent due to the synergistic effects of the composites. [4]
REFERENCES
[1] Cui,Z.M.; Li,L.J.; Arumugam M.;John.B. G. J. Am. Chem. Soc., 2015, 137, 7278.
[3] Chui, S.; S. Y., Lo, S. M. F., Charmant, J. P. H., Orpen, A. G., Williams, I. D. Science,
1999, 283, 1148.
[4] Dorina, F.; Sava, G.; Tina, M.; Nenoff. etc., Chem. Mater., 2015, 27, 2018.
[5] Gu, X.;Lu,Z.H.; Jiang,H.L.; Akita,T.; Xu,Q.J. Am. Chem. Soc., 2011, 133, 11822.
P2-45
Facile Synthesis of Mn3O4 /CNT Nanocompositeas High Performance
Anode Materials for Lithium Ion Batteries
Lihua Zhang, Sisi Wu, Yi Wan, Yifeng Huo, Yaochong Luo, Mingyang Yang,
Zhouguang Lu*
Department of Material Science and Engineering, South University of Science and
Technology of China, No.1088 Tangchang Blvd, Nanshan District, Shenzhen, 518055
P.R. [email protected]
Abstract
It is very important to explore cost-effective and high capacity and stable anode
materials for lithium ion batteries from ear-abundant resources. Here we report a facile
ball-milling method to prepare Mn3O4/CNT nanocomposites from some waste resources
like amorphous manganese oxide from recycled batteries or electrolytic manganese
industry. The obtained Mn3O4/CNT nanocomposites were intensively investigated as
anode materials for lithium-ion
batteries and supercapacitors. In these
Mn3O4/CNTs nanocomposites with a
unique bird nest architecture, the CNTs
work as electrical wiring branch. This
provides electron efficient transport
pathway and accommodate a large
volume change during the conversion
reactions. While the ultrafine Mn3O4
nanoparticles grafted onto the CNTs
ensure high specific capacity.
Therefore, exceptional high capacity
(>1000 mAh/g) and extremely stable
cycling were achieved.
Acknowledgements
This work was supported by the Science and Technology Innovation Foundation for the Undergraduates of
SUSTC (2014S07), the Shenzhen Peacock Plan (KQCX20140522150815065), the Natural Science
Foundation of Shenzhen, and the startup of The South University of Science and Technology of China.
REFERENCES
[1] Wang, Hailiang, et al. J. Am. Chem. Soc.132.40 (2010): 13978-13980.
0 400 800 1200 1600 20000.0
0.5
1.0
1.5
2.0
2.5
3.0
Vo
lta
ge
(V
vs
. L
i/L
i+)
Specific capacity (mAh/g)
1
2
3
4
5
Mn3O
4/CNT ball mill 8h
Fig. Galvanostatic voltage profiles of the first 5 cycles’ of the
Mn3O4/CNT nanocomposite cycled between 0.01 and 3V.
P2-46
Synthesis of bimetallic carbon nanocomposites as efficient
electrocatalyst for oxygen reduction reaction
Sisi Wu, Yifeng Huo, Yaochong Luo, Lihua Zhang, Yi Wan, Lujie Cao, Zhouguang Lu*
Department of Material Science and Engineering, South University of Science and Technology of China, Shenzhen, 518055 P.R. China.
ABSTRACT
On facing the increasing and alarming demand of energy, alternative energy conversion and storage systems including fuel cell and metal-air battery are regarded as
promising candidate.[1][2] However, the sluggish oxygen reduction process impedes the further study and improvement to a great extent and it remains imperative to develop
electrochemical oxygen reduction reaction (ORR) catalyst with high activity at a low cost. Here we reported a non-precious bimetallic carbon nanocomposites derived from some organic-inorganic composites by thermal treatment as high-performance catalyst for ORR.
The nanocomposites of various compositions were investigated for catalytic activity and the optimal sample exhibited very promising high performance. Even though pure copper
and nickel metals alone are candidate as non-precious ORR catalyst, our nanocomposites take advantage of both constituents and exhibit much better performance than that of the single component counterparts in terms of current density and onset voltage. Moreover,
the number of electron transfer (~4) suggested a high ORR catalytic efficiency, similar with commercial palladium black. These results reveal an effective strategy to promote
the activity of non-precious metals for ORR-based applications.
REFERENCES
[1] Liang, Y.; Li, Y.; Wang, H.; Zhou, J.; Wang, J.; Regier, T.; Dai, H., Nat Mater. 2011,
10 (10), 780-6;
[2] Zhang, T.; Cheng, F.; Du, J.; Hu, Y.; Chen, J., Advanced Energy Materials. 2015, 5
(1), 9.
Acknowledgements
This work was supported by the Science and Technology Innovation Foundation for the Undergraduates of SUSTC (2014S07), the Shenzhen Peacock Plan
(KQCX20140522150815065), the Natural Science Foundation of Shenzhen, and the startup of the South University of Science and Technology of China.
P2-47
Meeting pressure and temperature gaps, operando FTIR-MS instrument
measurement Y. Yang1,2; C. Mims3; C. Peden1; D. Mei,1 C.T. Campbell5, J. Kwak1,4;
1. Pacific Northwest National Laboratory 2. ShanghaiTech University
3. University of Toronto, Canada
4. Ulsan National Institute of Science and Technology, Korea
5. University of Washington
The Holy Grail in catalysis is to understand the relationship between surface structure
and catalytic activity or selectivity well enough to design better catalysts. As an
approaching to meet the temperature and pressure gaps, in last few years, an apparatus
has been developed and applied for operando catalyst kinetics studies by employing both
in-situ transmission FTIR probe of surface species and mass spectrometric (MS)
detection. This apparatus enables surface kinetics measurements such as steady state
isotope transient kinetic analysis (SSITKA) under high pressure and temperature
conditions.
Two kinetics studies will be discussed in this presentation. The first case is methanol
synthesis applying Cu catalyst, CO2+ 3H2 MeOH+ H2O. Most previous proposed
models agree that formates formed from H2/CO2 lead to products, methanol/H2O thus
surface formate has long been considered a key intermediate in the mechanism. While
confirming previous formats decay rate under hydrogen exposure, our results further
indicate that no methanol is produced by exposure of formate containing adlayers (both
from formic acid and by H2:CO2 catalysis to 6 bar dry hydrogen). In addition we have
performed similar titration experiments with an array of different reactive gases which
include all of the species present during this catalysis process. These results clearly
indicate that formate is a spectator species during methanol synthesis on copper. In the
second case, activity of methanol adsorbates on WO3 surface was investigated. Methanol
on most Lewis acid sites of metal oxides was believed to be dead species because of its
overnight stability in isothermal desorption process. However, its behavior was found
totally different in a SSITKA experiment with isotopic deuterated methanol exchange
(CD3OH/CH3OH) induced. Operando IR results shows with constant methanol partial
pressure (1 torr) in ambient flow while DME synthesis processed, surface methanol and
methoxy species by deuterated flow are by far much faster. Measured isotope
displacememnt time constant for methoxy was ~700 s and that for methanol was ~1700 s.
These preliminary results indicate that the methanol and methoxy are by far more active
(>100X) on a crowdie surface with gas phase methanol exposing comparing a surface
with slightly lower coverage and no methanol exposure. By direct comparison with
results from traditional elementary step experiments, both cases are strong examples that
an operado system, i.e., instrumentation under reaction conditions, is critical for
understanding the mechanism of some surface species in a catalytic process.
P2-48
A Flexible Ligand-based Wavy Layered Metal-Organic Framework for
Lithium-ion Storage
Tiance An, Yuhang Wang, Jing Tang, Yang Wang, Lijuan Zhang*, and Gengfeng Zheng*
Laboratory of Advanced Materials, Fudan University, Songhu Road 2205, Shanghai,
200438, China. Email: [email protected], [email protected]
ABSTRACT
The potentials of developing MOF-based energy storage materials such as lithium-ion batteries (LIBs) have been driving abundant research interest recently,[1] due to their uniform structures, high surface area and tunable porosities.[2] The metal cations in the MOF structures can serve as active sites for redox reactions, and the open crystal frameworks provide efficient and reversible insertion and extraction of ions in the either aqueous or organic electrolytes as well.[3-5] However, a substantial challenge for direct utilization of metal-organic frameworks (MOFs) as lithium-ion battery anodes is to maintain the rigid MOF structure during lithiation/delithiation cycles, whereas the three-dimensional rigid ones usually suffer from pulverization and lose their XRD patterns.[6] In this work, we developed a flexible, wavy layered nickel-based MOF (C20H24Cl2N8Ni, designated as Ni-Me4bpz) by a solvothermal approach of 3,3’,5,5’-tetramethyl-4,4’-bipyrazole (H2Me4bpz) with nickel(II) chloride hexahydrate. The obtained MOF materials (Ni-Me4bpz) with metal azolate coordination mode provide 2-dimensional layered structure for Li+ intercalation/extraction, and the H2Me4bpz ligands allow for flexible rotation feature and structural stability. As a result, lithium-ion battery anodes made of the Ni-Me4bpz material demonstrate excellent specific capacity and cycling performance, and the crystal structure is well preserved after the electrochemical tests, suggesting the potential of developing flexible layered MOFs for efficient and stable electrochemical storage. REFERENCES
[1] Pasta, M.; Wessells, C. D.; Liu, N.; Nelson, J.; McDowell, M. T.; Huggins, R. A.; Toney, M. F.; Cui, Y. Nat Commun. 2014, 5. [2] Furukawa, H.; Cordova, K. E.; O’Keeffe, M.; Yaghi, O. M. Science. 2013, 341. [3] Férey, G.; Millange, F.; Morcrette, M.; Serre, C.; Doublet, M.-L.; Grenèche, J.-M.; Tarascon, J.-M. Angew. Chem. Int. Ed. 2007, 46, 3259. [4] Liu, Q.; Yu, L.; Wang, Y.; Ji, Y.; Horvat, J.; Cheng, M.-L.; Jia, X.; Wang, G. Inorg. Chem. 2013, 52, 2817. [5] Nie, P.; Shen, L.; Luo, H.; Ding, B.; Xu, G.; Wang, J.; Zhang, X. J. Mater. Chem. A. 2014, 2, 5852. [6] Li, X.; Cheng, F.; Zhang, S.; Chen, J. J. Power Sources. 2006, 160, 542.
P2-49
Control the structure morphology of biomass-derived carbon for
supercapacitors
Yijin Caia,Mingtao Zheng*ab, Bingfu Leiab and Yingliang Liu*ab
(aDepartment of Materials Science and Engineering, College of MaterialsandEnergy,South China Agricultural University, Guangzhou 510642, China. E-mail:[email protected]; [email protected]; [email protected] [email protected];Fax: +862085280319; Tel: +862085280319
bGuangdong Provincial Engineering Technology Research Center for OpticalAgriculture, Guangzhou 510642, China)
In our work , we took the seaweed as carbon precursor, dipped in the lowconcentration of KOH solution and dried by freeze drying[1]. With different annealingtemperature, we could get the different structure morphology, graphene-likeframework and three-dimensional honeycomb-like hierarchically structured carbon,respectively[2]. The resulted samples have high specific surface area(2305 m2 g-1 and1653 m2 g-1), proper pore volume(1.00 cm3 g-1 and 1.32cm3 g-1) and excellentelectrochemical performance. The high specific capacitance of this two samples are280 F g-1 and 321 F g-1 at the current density of 0.5 A g -1, respectively.
Fig. 1(a) and (b) are FESEM images of S700 and S800, (c)N2adsorption-desorption isotherms and (d) galvanostatic charge/discharge (GCD) curvesof S700 and S800, respectively.(700 and 800 are refer to the annealing temperature)
REFERENCES[1] C. Long, X. Chen, L. Jiang, L. Zhi and Z. Fan, Nano Energy, 2015, 12,141-151.[2]P. Hao, Z. Zhao, Y. Leng, J. Tian, Y. Sang, R. Boughton, C.Wong, H. Liu and B.Yang, Nano Energy, 2015,15,9-23.
P2-50
Freestanding 3D graphene/cobalt sulfide
composites for supercapacitors and hydrogen
evolution reaction Yang Wanga, Jing Tanga, Lijuan Zhanga*
and Gengfeng Zhengab*
aLaboratory of Advanced Materials, bDepartment of Chemistry, Fudan University,
Shanghai 200433, People's Republic of China. E-mail: [email protected]; [email protected]
ABSTRACT
The development of lightweight, flexible, electrochemically active materials with
high efficiency is important for energy storage and conversion [1-5]. In this study, we
report the fabrication of a freestanding, 3-dimensional graphene/cobalt sulfide nanoflake
(3DG/CoSx) composite for supercapacitors and hydrogen evolution catalysts. The
graphene framework formed by chemical vapour deposition provides superlight, highly
conductive electron transport pathways, as well as abundant pores for electrolyte
penetration. The densely patterned cobalt sulfide nanoflake arrays grown by
electrodeposition offer a large surface area for electrochemical reactions, high
theoretical capacitance and efficient hydrogen evolution catalytic activity. As a
proof-of-concept, supercapacitors made of the 3DG/CoSx composites deliver a high
specific capacitance of 443 F g-1 at 1 A g-1, with excellent capacity retention of 86%
after 5000 cycles and mechanical flexibility. In addition, the 3DS/CoSx composites
show attractive features as hydrogen evolution catalysts, with a low overpotential of
0.11 V and a Tafel slope of 93 mV dec-1.
REFERENCES
[1] Beidaghi, M. and Gogotsi, Y. Energy Environ. Sci., 2014, 7, 867.
[2] Wang, X.; Lu, X.; Liu, B.; Chen, D.; Tong, Y. and Shen, G. Adv. Mater., 2014, 26,
4763.
[3] Gao, M.-R.; Xu, Y.-F.; Jiang, J. and Yu, S.-H. Chem. Soc. Rev., 2013, 42, 2986.
[4] Liu, L.; Niu, Z.; Zhang, L.; Zhou, W.; Chen, X. and Xie, S. Adv. Mater., 2014, 26,
4855.
[5] Zhang, G. Q.; Wu, H. B.; Hoster, H. E. and Lou, X. W. Energy Environ. Sci., 2014, 7,
302.
P2-51
Metal–Organic Frameworks as Cathode Materials for Li–O2 Batteries
Doufeng Wu, Ziyang Guo, Xinbo Yin, Qingqing Pang, Binbin Tu, Lijuan Zhang, Yong-Gang Wang, Qiaowei Li
Department of Chemistry Fudan University, 220 Handan Road , Shanghai 200433 ,
China [email protected]
ABSTRACT Li-O2 batteries have attracted extensive research owing to their higher theoretical gravimetric energy density than that of other chemical batteries. We selected MOF-5, HKUST-1, and M-MOF-74 (M =Mg, Mn, Co) as possible Metal–organic frameworks (MOFs) for the O2 electrode materials and assessed how their structural attributes impact performance.
We found that MOFs with open metal sites enrich the population of O2 in the pores significantly and assist the Li–O2 reaction when employed as a cell electrode material. A primary capacity of 9420 mA h g−1 is achieved in a cell with Mn-MOF-74; more than four times higher than the value obtained in a cell without an MOF. REFERENCES [1] Wu, D.; Guo, Z.; Yin, X.; Pang, Q.; Tu, B.; Zhang, L.; Wang, Y.-G.; Li, Q. Adv. Mater. 2014, 26, 3258.
P2-52
Structure and Electrochemical Property of Li1+xAlxGe2-x(PO4)3 Solid
Electrolytes Synthesized by Different Methods
Yingjia Liu, Jian Chen*
Dalian National Laboratory for Clean Energy, iChEM, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian,116023
E-mail: [email protected]
ABSTRACT
All-solid-state lithium secondary batteries are expected as the new generation
batteries due to their high safety and durability. The solid electrolyte is the key
component to control the battery properties. NASICON-type Li1+xAlxGe2-x(PO4)3
(LAGP) solid electrolytes are the promising candidates because they own a high ionic
conductivity.
However, the LAGP materials were usually synthesized by melt-quenching method,
which involves a high-temperature melting process (1350-1500oC) and long annealing
time[1,2]. The high melting temperature could result in lithium losses. Consequently, it is
required to develop low-temperature preparation techniques, e.g. the Pechini method,
etc.
In this work, the LAGP solid electrolytes were synthesized by a modified sol-gel
method and the conventional solid-state reaction, respectively. Effects of the synthesis
routes on the microstructure and electrochemical properties were investigated. Details
focused on their structure-properties relationships.
We expect this work can provide an effective preparation choice for high-
performance solid electrolytes.
REFERENCES
[1] Fu, J. Solid State Ionics 1997, 104, 191.
[2] Chen, H.; Tao, H.; Wu, Q.; Zhao, X. J. Am. Ceram. Soc. 2013, 96, 801.
P2-53
Fiber-shaped polymer light-emitting electrochemical cells
Zhitao Zhang, Huisheng Peng
Department of Macromolecular Science and Laboratory of Advanced Materials, Fudan University, Shanghai 200438, China; E-mail: [email protected].
ABSTRACT
Wearable light-emitting electronics have been developed for various applications, including microelectronics, transport, biomedicine and aerospace. Traditional planar light-emitting electronics cannot meet the increasing requirements for such an application, such as light weight and weavability. To this end, advances in the textile industry have suggested a useful direction in which to pursue a solution: if the light-emitting devices are made into a continuous fiber through all-solution-based processes, they can be woven into various textiles.
Herein, a new family of fiber-shaped polymer light-emitting electrochemical cells
(PLECs) has been fabricated with a coaxial, flexible, transparent and continuous carbon nanotube sheet as the electrode. The fiber-shaped PLECs can provide a variety of tunable colors, and they can be further woven into flexible and lightweight electronic textiles to satisfy the requirement of the portable products.
Figure 1. a) Textile under bending. b–d) Two fiber-shaped PLECs with different colors being selectively illuminated. e–i) Fiber-shaped PLECs being woven into a ‘FUDAN’ pattern. REFERENCES
[1] Zhang, Z.; Guo, K.; Li, Y.; Li, X.; Guan, G..; Li, H.; Luo, Y.; Zhao, F.; Zhang, Q.; Wei, B.; Pei, Q.; Peng, H. Nature Photon. 2015, 9, 233.
[2] Zhang, Z.; Chen, X.; Chen, P.; Guan, G.; Qiu, L.; Lin, H.; Yang, Z.; Bai, W.; Luo, Y.; Peng, H. Adv. Mater. 2014, 26, 466.
[3] Zhang, Z.; Li, X.; Guan, G.; Pan, S.; Zhu, Z.; Ren, D.; Peng, H. Angew. Chem. Int. Ed. 2014, 53, 11571.
P2-54
The preparation of amorphous MoSx/graphene aerogel and the
application in Li-O2 battery
Li Liang-yu, Chen Chun-guang, Lin Xiu-jing, Huang Tao, Yu Ai-shui*
Department of Chemistry, Shanghai Key Laboratory of Molecular Catalysis and
Innovative Materials, Institute of New Energy, Fudan University, Shanghai 200438
E-mail:[email protected]
ABSTRACT
Graphene has great potential in the field of energy storage due to the unique
physical structure. The large number of tunnels, pores and defects can provide access
and catalytic active sites for oxygen diffusion and reduction. MoS2 is a typical layered
metal sulfide, which has been widely concerned for its applications in catalysis,
hydrogen storage and Li-ion battery electrode materials. Li Meixian [1] group found that
MoS2 can exhibit excellent ORR catalytic activity, thus provide the possibility of
application in Li-O2 battery.
In our work, one-step hydrothermal reaction was developed to synthesize
amorphous MoSx/graphene hydrogel and the final aerogel was obtained by
freeze-drying. As illustrated in fig. 1a, SEM shows that the MoSx/graphene aerogel has
a 3D-porous network with interconnected pores which in the range of several
nanometers to micrometers. Fig. 1b shows the electrochemical performance of the
MoSx/graphene aerogel at different current densities. At a current density of 0.05
mA/cm2, the capacity is about 6678 mAh/g. with the increase of the current density, the
capacity decreases gradually, at a current density of 0.2 mA/cm2, the capacity is still
3342 mAh/g reserved, suggesting a good rate performance of the aerogel.
0 1000 2000 3000 4000 5000 6000 70001.5
2.0
2.5
3.0
3.5
4.0
4.5
5.0
0.05 mA/cm2
0.1 mA/cm2
0.2 mA/cm2
0.5 mA/cm2
Voltage (
V)
Capacity (mAh/g MoSx + C
)
b
REFERENCES
[1] Wang, T. Y., Gao, D. L., Li, M. X., Chemistry-a European Journal, 2013, 19, 11939
a
P2-55
Li-rich Oxides with Excellent Performance Derived from Ni(OH)2/MnO2
Core-shell Precursors
Shifeng Yang, Jian Chen
Dalian National Laboratory for Clean Energy, iChEM, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian,116023
E-mail: [email protected]
ABSTRACT
The layered Li-rich oxides (LLO) materials xLi2MnO3•(1-x)LiMO2(M=Ni, Mn or Co, ect) can deliver a high reversible capacity(>250 mAh/g), which are considered as the most attractive cathode candidate for the lithium-ion batteries (LIBs). Based on the LLO cathode, LIBs can deliver a energy density over 250Wh/kg, and then can be used as power batteries in the electrical vehicles.
However, significant barriers such as poor cycling performance and inferior rate
capability of LLO materials severely restrict their practical application. Cyclic deterioration mainly results from the corrosion/fragmentation etched by acidic species in the electrolyte[1], which can be effectively improved by surface modification. During the LLO synthesis process, nickel can preferentially move and selectively segregate at the surface facets, and the segregation within the surface layer essentially leads to a higher lithium diffusion barrier and sluggish kinetics[2].
To improve the electrochemical performance of LLO materials, we fabricated
nano-sized 0.3Li2MnO3•(1-x)LiNi0.5Mn0.5O2 with a heterogeneous composition structure. Flower-like Ni(OH)2/MnO2 core-shell materials was first synthesized as the precursor (Figure 1), then the LLO materials with the size of 250-300 nm was obtained by the solid-state reaction of Ni(OH)2/MnO2 and lithium salts. The Ni(OH)2/MnO2 precursor with a core-shell structure could contribute to the LLO particles with a heterogeneous structure of Ni-rich core and Mn-rich shell. The prepared 0.3Li2MnO3•(1-x)LiNi0.5Mn0.5O2 delivered a high specific capacity over 275 mAh/g (Figure 2) and exhibited excellent cycling and rate performance. The capacity retained 96% of the initial capacity at 30 mA/g. Even at a higher current density of 300 mA/g, a specific capacity of 184 mAh/g could be achieved, maintaining 86% after 100 cycles.
REFERENCES
[1] Jianming Z.; Meng G.; Jie X.; et al. Nano Lett. 2013,13,3824 [2] Meng G.; Ilias B.; Arda G.; et al. Nano Lett. 2012, 12, 5186
Figure 1 SEM image of Ni(OH)2/MnO2 precursor Figure 2 charge-discharge curves of the final LLO material
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