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EPSRC Centre for Doctoral Training in ‘Functional Materials and Devices’ ‘From Materials to Devices’ 25 th Feb 2013 Director: Ian M. Reaney
EPSRC Centre for Doctoral Training in ‘Functional Materials
and Devices’
‘From Materials to Devices’
25th Feb 2013
Director: Ian M. Reaney
EPSRC is seeking to invest £350m in
Centres for Doctoral Training to address
priority areas. CDTs will train the research
leaders of the future and equip them with
the knowledge, skills and creative
approaches the UK requires.
“to produce internationally leading PhD graduates in Functional Materials and Devices with a wide range of skills and knowledge to drive innovation in SMEs and OEMs
“To create the next generation of leaders for UK PLC in the development of an expanding Functional Material and Device market”
Key Aims
Mono-institutional
Based mainly in
• Materials Science and Engineering (MSE)
• Electrical and Electronic Engineering (EEE)
• Chemical and Biological Engineering (CBE)
Links to other Department/Faculties/Universities will be made as appropriate for the project.
Existing infrastructure to establish a centre which is internationally leading in all aspects of the research and training required to discover and exploit functional materials.
50+ students- 1st cohort to start in October 2014 for 4 year PhDs
The CDT fits directly into Faculty/Departmental priority areas
since it builds on the large funding in:
• Functional Materials (~£20M over 10 years, MSE)
• EPSRC National Centre for III-V Technologies (>£14M over 10 yrs, EEE)
• Mercury Centre for Additive Manufacturing (~£10M, MSE)
• Sheffield NanoLAB (£3M over 8 years, MSE, Programme Grant on CO2 utilisation (£4.6M, CBE)
• Communications Group (£4M over 8 years, EEE)
• Sorby Centre for Microanalysis
• Outcome of £4M Marie Curie ITN (M2D) will be known by EPSRC’s April EOI deadline
Infrastructure
TEM
AFM/Nano indentation
5 FEG SEMs 2 with
EBSD:
Quanta 3D Dual
Beam FIB
4 TEMs
Bruker AFM
Hysitron
Nanoindentation
Contour 3D
(interferometer)
SEM
Mercury Centre for Innovative Materials and Advanced Manufacturing
Micro-scale 3D printing
Spark Plasma Sintering
Laser ALM
Vacuum Furnace
+ tape casting, screen
printing, electrophoretic
deposition, slurry mixing
Critical mass for Functional Materials and Devices:
• Functional Ceramics (Reaney, West, Sinclair, MSE)
• Magnetic sensors, biosensors (Allwood, Morley, Gibbs, Haycock, Matcher, MSE)
• Functional Polymers (Ungar, Zheng, MSE, Iraqi, Chem.)
• Nanofabrication (Hogg, Groom, EEE)
• Communications (Langley, Seed, Williams, Tennant, EEE)
• Multiscale Modelling (Harding, Freeman, Dean, MSE)
• Additive Manufacturing (Todd, Rainforth, MSE)
• Nano-testing and Fabrication (Inkson, Moebus, MSE)
• Electrolysis and Fuel cells (Allen, Elder CBE)
• Energy Storage Devices (Hall, CBE)
• III-V Semiconductor Functional Materials and Devices (Wang, EEE)
• Materials characterisation (Rainforth, Reaney, Inkson, MSE)
Staff & Expertise
Sensors/Actuators, Theme Leader Dan Allwood
initially piezo. sensors and actuators but anticipate strategic expansion into chemical and bio sensors
Energy Storage and Generation, Theme Leader - Derek Sinclair
Initial focus piezo. harvesting, thermoelectric generators, batteries, CO2 utilisation, supercapacitors.
Sustainability, Theme Leader = Rachel Elder
Reduction in RE content of Functional Materials, reduction in raw energy costs for materials and device fabrication. Manufacturing research to reduce costs.
Communications, Theme Leader = Richard Langley
Antennas, LTCC modules, rf harvesters, microwave ceramics, CAD, State of the anechoic chamber measurements.
Characterisation, Theme Leader = Mark Rainforth
Scanning/Transmission electron microscopy, EBSD, Raman, XRD, ND
What the CDT Will Do
‘The CDT will have a mix of industrial and non-industrial collaborators to undertake fundamental blue skies as well as applied projects’ ‘We will focus on a ‘best with best’ approach for our academic collaborators seeking out top-ranked people and institutes with whom we will co-fund projects with the proviso that all students will graduate from Sheffield’ ‘Industrial and/or academic secondments will be built into all PhD programmes which will form an intrinsic part of the training and research experience’
Studentship £30k per annum.
EPSRC provision £20k per annum
External Contribution £10k per annum
What do you get for your money!
Our Model
Initial contact through Director or CDT Manager
Appropriate academic supervisor will be identified
Industry, academic supervisor and theme leader design a 4 year project, to include industrial/academic placements as appropriate
Student will undertake research and be taught appropriate leadership, soft and technical skills to create a ready-made potential employee who has already generated valuable, relevant R&D
Sponsors are invited to participate in the Industrial Advisory Board
Procedure
Expressions of Interest to date:
Pennsylavania State University, TU Darmstadt,Oregon State University, Rutherford Appleton Laboratory, Powerwave, Sarantel, Johnson Matthey, Morgan Electroceramics, Qinetic, IQE Plc, CST Global, Faradion, Euro Thermodyanamics, Dyson Technical Ceramics, SUSS Microptics, Avago Technologies,
Q&A
Prof. Richard Langley
COMMUNICATIONS GROUP
University of Sheffield 10 academic staff
Prof Richard Langley (Group leader)
Prof Jie Zhang Prof Tim O’Farrell
Dr Greg Cook Dr Alan Tennant
Dr Salam Khamas Dr Lee Ford Dr Wei Liu
Dr Mohammed Benaissa Dr Xiaoli Zhu
Electromagnetics Projects
• Miniaturised platform tolerant antennas
• Textile antennas
• Reconfigurable mobile phone antennas
• Elastic/conformable antennas
• Smart antennas
• Smart materials
• Smart structures for secure communication
INDUSTRIAL COLLABORATORS
Alcatel-Lucent, Antenova, BAE Systems, BBC,
British Gas, BT, Building Research Establishment,
DSTL, Ember, Fujitsu, Harada Industries, Huawei,
NEC, NSN, Orange, O2, Qinetiq, Ranplan, Selex,
Thales, T-Mobile, Toshiba, Vodafone, Zigbee
Alliance
Electronic tuning of the dielectric –
Liquid Crystal (Antenova Ltd)
SIMILAR RESULTS AT 5 GHz
0-10V bias
RECONFIGURABLE ANTENNA USING SMART
MATERIAL
0.8 1 1.2 1.4 1.6
Frequency GHz
-30
-25
-20
-15
-10
-5
0
Refl
ecti
on
co
ef
dB
LegendPIFA1 strip 38mm1 strip 48mm2 strips 38/48mm2 strips 38/58mm3 strips
Elastic Antennas
• 50/100 nm Au on
pillars PDMS substrate
Miniaturised platform tolerant antennas
λ/10
Antenna: split ring dipole
NOTE -TUNABLE
200 300 400 500 600 700
Frequency (MHz)
-18
-15
-12
-9
-6
-3
0
S P
ara
mete
r (d
B)
1V
1.5V
2V
3V
4V
6V
12V
-30
-25
-20
-15
-10
-5
0
350 400 450 500 550
S11
Mag
nit
ud
e (
dB
)
Frequency (MHz)
1V 1.5V 2V 2.5V 3V 4V 9V
Miniature platform tolerant
antennas
Period = 10mm (λ/70) C= 15pF
120 x 80 x13.2 mm
λ/6 x λ/9
400 420 440 460 480 500
Frequency (MHz)
-180
-135
-90
-45
0
45
90
135
180
Refl
ecti
on
Ph
ase
UC-EBG Reflection Phase
3.2mm
6.4mm
450MHz
Tunable
Artificial magnetic conductor (AMC)
Tunable multi-band PIFA Antenna for
80MHz to 2200 MHz (Antenova)
500 1000 1500 2000 2500
Frequency / MHz
-40
-35
-30
-25
-20
-15
-10
-5
0
S11
/ dB
0 100 200 300 400 500 600 700 800-35
-30
-25
-20
-15
-10
-5
0
Miniature AMC (meta-material)
400 420 440 460 480 500
Frequency (MHz)
-180
-135
-90
-45
0
45
90
135
180
Refl
ecti
on
Ph
ase
UC-EBG Reflection Phase
3.2mm
6.4mm
AMC is also tunable
3-D Antennas
15mm 15mm
Miniaturisation, bandwidth
Wearable Antennas
Dual band at 2.45GHz and 5.8 GHz
Antennas manufactured on or in clothing
using standard materials such
as felt with conducting material Zelt.
Conducting textiles
Knitted X band waveguide
Knitted textile high impedance surface
(AMC)
Conducting textiles
Knitted textile with embedded pin diodes
surface knitted from conducting and insulating yarns
Conducting textiles
Structural textiles
conducting ground-plane
spacer incorporating structural fibres and conducting vias
Conducting textiles
Embedding a semiconductor device into a multi-filament
yarn
FACILITIES
• Anechoic chambers for
antenna measurements
• 1.5km test range at Buxton
• Open road chamber at Buxton
(400MHz up)
• EM characterisation of both
low and high loss materials
• Software – commercial and
home grown
FUNCTIONAL MATERIALS
• Tunable antenna systems
• New Meta-materials
• Miniature structures
• Nano based materials
• Elastic antennas
• Wearable antennas
• Smart materials
In Numbers
• Academics
– 11 EEE, 3 Physics
• ~£3M per year EPSRC, BBSRC, Royal Society,Royal
Academy of Engineering, EU, Industrial
• ~15 PDRAs
• ~30 PhD Students
Facilities - Cleanrooms
~£6M Cleanrooms
~£20M of semiconductor tools
III-V Epitaxy
E-beam lithography
Dielectrics
Etch
Research
• Fundamentals – light-matter
• Technology & manufacture
– Epitaxy, device fabrication
• Devices for new applications
– Communications, lighting,
power electronics, biomedical
imaging, sensing,
Our Product
• World class engineers
and scientists
• Academic leaders
• Industrial leaders
Electroceramics at Sheffield
Tony West
0114 222 5501
Core expertise:
• Discovery and development of new materials for:- thermistors, actuators, sensors, antennas, capacitors, low temperature co-fired ceramics, Li batteries, fuel cells, thermoelectrics, memristors
• Fundamental science to prototype devices
• Full range of synthesis, processing, characterisation and property measurement techniques
The Electroceramics group consists of > 25 researchers and is led by: Ian Reaney (processing and devices); Tony West (crystal chemistry); Derek Sinclair (functional property measurements); the group collaborates widely, especially with John Harding (modelling) and Mark Rainforth (microscopy); also with Andy Bell (Leeds: thin film fabrication and electrical property measurements); Clive Randall and colleagues (Penn State USA, centre for dielectric studies)
We have expertise in:
Microscopy: full range of scanning and transmission electron microscopes (including aberration corrected)
Physical Measurements: Impedance Spectroscopy; Seebeck; transport number; piezoelectric coefficients; P-E hysteresis loops; cyclic voltammetry; thermal conductivity
Ceramic Processing: mills and furnaces; cold and hot isostatic presses; spark plasma sintering; tape casting + screen printing; aerosol jet printing.
Structural characterisation : X-ray and Electron Diffraction; Raman Spectroscopy; Analytical Electron Microscopy; Thermal Analysis.
• Excellent track record in working with Industry
KTPs with AVX Ltd (Multilayer Ceramic Capacitors); Sarantel Ltd (Antennas); Ilika (High throughput synthesis/screening of oxides)
Ian Reaney/Sarantel won the ‘Best KTP building on EPSRC funded research 2008’
Contract work with Powerwave
Sponsored PhD projects with Powerwave, Morgan Electroceramics, GEC thermoelectrics, Sarantel Ltd
EU grant with STMicroelectronics
43
Some current PhD topics:
• New materials for Li battery components
• Memristive phenomena in oxide ceramics
• Gas sensors based on stannate systems
• Doping-property correlations in Ba titanate systems
• New ferroelectric and antiferroelectric materials
• Structure-property relations in rare earth-doped BiFeO3
• High permittivity ceramics for dielectrically loaded GeoHelix antennas
• Ruddlesden-Popper structured thermoelectric oxides
• Effect of processing conditions on structure/properties of K Na niobate ceramics
• Defect chemistry of sodium bismuth titanates
• New sillenite structures for low temperature cofired ceramics
• Thermoelectrics based on hexagonal perovskites
Selection of current activities in the Sinclair group:
1. New Materials: structure-composition-property relationships.
(a) hexagonal perovskites (high permittivity materials)
(b) EuTiO3 (multiferroic)
2. New understanding: modelling + experimental
(a) Defect chemistry of BaTiO3
(b) Finite Element Modelling of electroceramics to simulate Impedance data.
3. ‘Target’ applications:
(a) Electrolysis cells
(b) Thermoelectrics
Material Q.f.
(GHz)
τf
(ppm/K)
εr
Ba(Mg1/3Ta2/3)O3 200,000 0 24
Ba(Co,Zn)1/3Nb2/3 O3
90,000 0 34
0.7CaTiO3 - 0.3NdAlO3 45,000 0 45
Ba8Nb4Ti3O24[1] 25,000 +100 46
Sr4LaTi4O15[2]
50,000 -14 43.8
Ba0.2La4Ti3.2O12.6[3] 87,000 -17 44
[1] R. Rawal et al, J. Am. Ceram. Soc., 89 (2006) 336.
[2] I.N. Jawahar et al., J. Mater. Res., 17 (2002) 3804.
[3] H. Yamada et al, J. Eur. Ceram. Soc., 26 (2006) 2059. 12R-La4Ti3O12 + BaTiO3
• 20 < εr < 50 ; Q > 30,000 at 1 GHz ; τf ~ 0 ppm/K
Commercially available cubic
perovskites
Reported Hexagonal Perovskites
Motivation: to study high permittivity (non-ferroelectric) hexagonal perovskites
: searching for new microwave dielectric resonator materials.
Our aim is to use oxides for
(i) high temperature applications and/or
(ii) lower cost devices near RT albeit with lower zT
• Hexagonal perovskites for anisotropy and intergrowths to lower κ
• Can make p-type (based on Co3+/Co4+) or n-type (based on Ti3+/Ti4+)
• Seebeck coefficient ~ + 100 to 120 μV/K (25 - 400 oC)
• Similar to NaxCoO2 wrt mixed Co3+ and Co4+ ions (magnetic entropy)
6H (hexagonal) BaTi1-yCoyO3-d (0.10 ≤ y ≤ 0.40)
YSZ
GDC
Electrolysis
Fuel Cell Mode : mix fuel (H2, CO, etc) and air to generate electricity (and H2O)
Electrolysis Mode: take ‘wet CO2’ and apply electricity to generate fuel (H2, CO)
Approach: find the best materials for electrolysis mode and/or reduce operating temperature.
Search is on to replace YSZ/GDC as the electrolyte. Ceramic bilayers are potentially interesting.
GDC REB
Conductivity : REB > GDC
Stability in low pO2: GDC > REB
Bilayers with different thickness may be a solution.
DEK 247 semi-automatic screen printer Mistler Inc. TTC-1200 Table-top caster
• Tape cast YSZ electrolyte
• Single layer and bilayer (isostatically pressed) electrolytes
Impedance measured using Pt electrodes
• Screen printed Ni-YSZ & LSM-YSZ electrodes
• Cells ready for testing…
Project Progress: Button Cells (~70 mm)
Dr. Dan Allwood
Magnetism in Sheffield
Materials Science
Nanotechnology
Energy
Sensors
EF
Modelling
People
• Prof Mike Gibbs
• Dr Dan Allwood
• Dr Nicola Morley
• Dr Tom Hayward
• Dr Julian Dean
• Dr Colin Freeman
• Prof Gillian Gehring
Facilities
• Fabrication
– Thin film deposition
– Nanoscale patterning
– Advanced manufacturing of bulk
• Analysis
– Magneto-optical magnetometry
– Magnetoresistance measurements
– Scanning probe microscopy
– Structural characterisation
Modelling
• Ab initio and molecular dynamics
• Finite element modelling Crystal structure Anisotropy
Dynamics
Stress Stray field
Materials Science
• Spintronics – ‘spin electronics’
– Exhibit ‘magnetoresistance’
– Organic spintronics
• Organic conduction layers
• Mechanism of electron transport
– Half-metal ferromagnets
• La0.7Ca0.3 MnO3 and Fe3O4
• Improved understanding improving MR
EF
FM
FM
Organic I
Materials Science
• Dilute magnetic semiconductors
– ZnO
– Magneto-optical interactions
– Doping concentration
• Interaction with cold atoms
– Reconfigurable atom optics
Materials Science
• Thermal effects in magnetism
– Stochasticity
– Biggest limitation to magnetic performance
-14 -7 0 7 140
10
20
Occ
ura
nce
s
Field Required to Change States (mT)
-14 -7 0 7 140
40
80
Occ
ura
nce
s
Field Required to Change States (mT)
Control-off Control-on
Materials Science
• Thermal effects in magnetism –
collaborators
Magnetic Imaging
Micromagnetic
modeling
Magnetic Imaging Multi-layer
magnetic devices
High-quality thin films
Perpendicular
anisotropy materials
Nanotechnology
• Magnetic nanowires
– Control and use of magnetic domain walls
NOT
NOT
NOT
NOT
NOT’
NOT
NOT
NOT
Fan
*
Magnetic logic Bio-manipulation
Energy
• Magnetic materials have a primary role in
energy economy:
– ‘Soft’ magnetic materials in transformers
– ‘Hard’ magnetic materials in motors &
generators
Toyota Prius hybrid
car
Washing
machine Wind
turbine
Hard disk
drive
Energy
• Meeting the ‘RE’ crisis
– Advanced manufacturing
– Non-uniform properties
– Materials design – expt & modelling
Sensors
• MagMEMS
– Based on ‘magnetostrictive film technology
Remote control
over film
stiffness
Sensors
• MagMEMS - cantilever
f0
0.162E
t2
l2 E
1
2
Sensors
• MagMEMS – cantilever
– Sensitive to chemical analyte
– TSB project for technology deployment
– FP7 with five EU companies in progress
MEMS
platform
smart magnetic
film
chemical
affinity layer
Sensors
• Nanoscale (organic) spintronics
– In-plane magnetoresistive devices
– Magnetic field sensors
– Standard devices with 0.3 % MR
– Latest devices with 400 % MR
Functional Polymers
Ahmed Iraqi,1 Abdulaziz Alghamdi,1 Hunan Yi,1 Solyman Al-Faifi,1 Darren
Watters,2 James Kingsley,2 David G. Lidzey2
1 Department of Chemistry, University of Sheffield, UK 2 Department of Physics and Astronomy, University of Sheffield, UK
CDT Industry open day 25th February 2013
Plastic solar cells
p-n junction is created by blends of two different materials, Donor (hole conducting)
and Acceptor (electron conducting).
DONOR: Conjugated Polymer e.g. Poly(3-hexylthiophene)
ACCEPTOR: Fullerene (C60) or its derivatives (PCBM)
Conjugation in polymers enables two
essential requirement:
• Photon absorption in the visible range
• Electrical charge transport
BAND GAP: > 1.9 eV PCE : 3-6%
Problem:
Low carrier mobility but……High
absorption coefficient and easy
processability. The structure of fullerene materials and conjugated polymers
used in organic solar cells.
S n
O
O n
Advantages
• Synthesis and processing less expensive
than inorganic crystal growth
• Potential for niche
properties
– Flexibility
– Colour
Plastic solar cells
Pictures from www.printedelectronicsworld.com and www.konarka.com
Working principles
Glass
ITO (anode)
organic semiconducting layer
Al-electrode (cathode)
Light
Factors affecting device operation
a. Energy gap of polymer donors
Solar Spectrum
S n
Poly(3-hexylthiophene),
the polymer most studied
in devices to date, does
not absorb light beyond
670 nm.
Factors affecting device operation
b. Offset of energy levels of donors and acceptors used
HOMO
HOMO
LUMO
LUMO
E
Donor Acceptor
VOC
- E ≥ 0.3 eV.
- If E too high, it is
energetically wasteful.
e: External Power Conversion efficiency
e = (VOC ISC FF) / Pin
VOC: Open Circuit Potential (V) ISC: Short Circuit Current (A/cm2)
FF: Fill Factor (Area under I/V curve); Pin: Incident light power (W/cm2)
(Scharber et al. Adv. Mater. (2006), 18, 789–794)
Design rules of donors for use in blends with
PCBM
P1 P2 PCDTBT
20 10 5 20 10 5 20 10 5
Concentration in mg/ml
P1 P2 PCDTBT
20 10 5 20 10 5 20 10 5
Concentration in mg/ml
N
C8H17 C8H17
nSS
N NS
C8H17O OC8H17
S S
N NS
C8H17O OC8H17
SS
N
C8H17C8H17
n
P1
P2
N
C8H17 C8H17
nSS
N NS
PCDTBT• Adsorb maximum sunlight.
• Control energy levels of HOMO and
LUMO levels of materials in blends.
• Control of morphology.
• Processability highly important.
Work at Sheffield on plastic solar cells
•. To develop new highly processable and efficient polymers for PV applications
and use Spray-Coating of active layers in solar cells as a new deposition method.
• Will provide better control of morphology of active layers and is an ideal method for
mass producing PV devices.
• Current film deposition techniques include:
Spin-coating
Ink-jet printing
Doctor-blade coating
Gravure contact printing
PP + PCBMPP +
PCBM PCBMPP+
PCBM
PP
(a) (b) (c)
(a) Spray-coating of the photovoltaic polymer
(PP) and the PCBM in a single step. (b) The
two materials being co-sprayed where they mix
in an aerosol phase. (c), PCBM is sprayed onto
a dry / wet PP film.
Work at Sheffield on plastic solar cells
Examples of systems investigated at Sheffield
NSe
NSN
Se
C8H15 C8H17
Se
NSN
Se
C8H15 C8H17
S
NSN
S
C8H15 C8H17
S
NSN
S
C8H15 C8H17C8H17OOC8H17
NSe
NSN
Se
C8H15 C8H17C8H17O OC8H17
Se
NSN
Se
C8H15C8H17C8H17OOC8H17
NS
NSN
S
C8H15 C8H17C8H17O OC8H17
NS
NSN
S
C8H15 C8H17
PCDTBT
n
P1
n
P2
n
P3
n
P7
n
P4
n
P6
n
P5
n
Absorption spectra of films
NSe
NSN
Se
C8H15 C8H17
Se
NSN
Se
C8H15 C8H17
S
NSN
S
C8H15 C8H17
NS
NSN
S
C8H15 C8H17
PCDTBT
n
P1
n
P2
n
P3
n
S
NSN
S
C8H15 C8H17C8H17OOC8H17
NSe
NSN
Se
C8H15 C8H17C8H17O OC8H17
Se
NSN
Se
C8H15C8H17C8H17OOC8H17
NS
NSN
S
C8H15 C8H17C8H17O OC8H17
n
P7
n
P4
n
P6
n
P5
NSe
NSN
Se
C8H15 C8H17
NS
NSN
S
C8H15 C8H17
PCDTBT
n
P1
n
Se
NSN
Se
C8H15 C8H17
S
NSN
S
C8H15 C8H17
n
P2
n
P3
Acknowledgments:
Abdulaziz Al Ghamdi David G. Lidzey
Hunan Yi James kingsley,
Solyman Al-Faifi Darren Watters,
Mohd S. Sarjadi (Physics & Astronomy, University of Sheffield)
Mohammed Almeataq
Funding:
Tours of research facilities
14:00 Ceramics laboratories- Prof. Ian Reaney
14:20 Mercury Centre for Advanced Manufacturing- Dr.
Martin Highett & Prof. Ian Reaney
14:50 Electron microscopy facilities- Prof. Mark Rainforth
15:20 Nanofabrication laboratories- Dr. David Childs
