Nanocrystallinity:
* Chemical intrinsic properties (Nanokinkendall effect)
* Calculated absorption spectra of quasispherical Au, Ag and Cu 5 nm nanoparticles: DDA
simulation
* The coherent acoustic phonons (l=0)
* Quadrupolar vibrational modes (l=2)
* Segregation processes during the supracrystal growth process
* High index Au nanocrystal superlattice plane
* Supracrystals mechanical properties
* Hierarchical elastic properties of supracrystals.
decahedron icosahedron Ino decahedraMarks decahedra cubooctahedron Troncated octahedron
Amorphous defects single crystals
Nanocrystallinity: Crystalline structure of nanoparticles
Chemical and physical intrinsic properties
Chemical intrinsic properties (Nano-kinkendall effect)
.Z. Yang, N. Yang and M.P.Pileni J.Phys.Chem.C., 2015, 119, 22249- 22260 Z. Yang, N. Yang, J. Yang, J. Bergström and M.P. Pileni Adv.Funct.Mater.,2015,
25, 891-897,Z .Yang, J.Yang, J.Bergström, K.Khazen, and M. P. Pileni Phys. Chem. Chem. Phys.,2014, 16, 9791-9796 Z .Yang, M ; Walls, I. Lisiecki, and M. P.
Pileni. Chem. Mater. 2013, 25, 2372-2377 , Z.Yang, I.Lisiecki, M. Walls, M.P. Pileni ACS Nano., 2013, 7, 1342–1350 I.Lisiecki, S.Turner, S.Balls, M.P.Pileni and
G.Van Tendeloo. Chem. Mat., 2009, 21, 2335-2338, I. Lisiecki, M. Walls, D. Parker and M.P. Pileni, Langmuir, 2008, 24, 4295-4299
yolk/shell Hollow: polycrystalline shellcore/shellsolid
Size
Kirkendall effect
2.2 Å
2.2 Å
3 nm3 nm
2.4
6 Å
2.4
6 Å
P. Yang, H. Portalès, and M. P. Pileni, J.Chem.Phys., 2011, 134, 024507-1/6,
N. Goubet, I. Tempra, J. Yang, G. Soavi, D. Polli, G. Cerullo and M. P. Pileni Nanoscale, 2015,7, 3237–3246.
Discrimination of decahedral MTPs from 5nm nanoparticles with mixed crystallinities
Calculated absorption spectra of quasispherical Au, Ag and Cu 5 nm nanoparticles:
DDA simulation
Ag CuAu
Cuboctahedron Truncated octahedron Decahedron Icosahedron Sphere
* The DDA target is represented by a finite periodic cubic array of
polarizable points (dipoles)
* The Maxwell’s equations of each dipoles are resolved considering the
interaction between the dipoles
* DDA is a flexible and powerful technique to calculate the scattering and
absorption for targets with arbitrary shapes
DDA Simulation
The Localized Surface plasmon resonance determined experimentally is:
* larger for polycrystalline phase than for single domain
* Does not depend on the nanocrystal size in the range from 5 to 12nm
ExperimentsNanocrystals dispersed in hexane
No changes in the coherent acoustic phonons (l=0)
n polycrystals = 517 3 GHz
n single crystal= 506 3 GHz
D. Polli I. Lisiecki, H. Portalès, G. Cerullo and M.P. Pileni. ACS Nano., 2011, 5, 5785-5791.
N. Goubet, C.Yan, D. Polli, H.Portalès, I.Arfaoui, G. Cerullo and M. P. Pileni Nano Lett., 2013,13, 504−508.
Du = 2.2 % n polycrystals= 6008 GHz
n single crystal= 58610 GHzDu = 2.3%
Frequency calculation by using Resonant Ultra-Sound (RUS) calculations:The model uses bulk elastic constants
Physical Review B 2009, 79.
npolycrystals= 692GHz
n single crystal= 682 GHz
Du = 1.5%npolycrystals= 599 GHz
* No dependencies on the acoutic phonons frequency with nanocrystallinity
* Significant damping faster for polycrystalline Au nanoparticles and none with Co nanoparticles
n single crystal= 554 GHzDu = 1.5
YanFen Wan; Hervé Portalès; Nicolas Goubet; Alain Mermet; Marie-Paule Pileni, Nano Research., 2013, 6, 611–618.
Segregation processes during the supracrystal growth process
200 μm
5 μm
5 μm
-300 -200 -100 0 100 200 300
Raman shift (GHz)
Inte
nsity
(arb
itra
ryu
nits)
-300 -200 -100 0 100 200 300
Raman shift (GHz)
Inte
nsity
(arb
itra
ryu
nits)
Single domain nanocrystals
Polycrystalline nanocrystals
low-frequency micro-Raman spectroscopy
Single domain supracrystals of single domain nanocrystals
Supracrystals film of polycrystalline nanocrystals
Single domain
nanocrystals 5 nm-1
5 nm-1Polycrystal nanocrystals
Orientational and translational orders Translational orders
N. Goubet, J.Yang, P.A.Albouy and M.P.Pileni Nano. Lett., 2014, 14, 6632-6638.
High index Au nanocrystal superlattice plane.
5 µm 5 µm
100 nm100 nm
Mixture single domain 8nm Co and
single domain 5nm Au nanocrystals
4 5 6 7 8 9 10
0
10
20
30
40
50
60
70
80
Popula
tion
Diameter (nm)
Mixture single domain 8nm Co and
polycrystalline 5nm Au nanocrystals
100 nmAu
Co
Single domain Polycrystal
1.1 ± 0.37 GPa 0.03 ± 0.01 GPa
N. Goubet, Yan, C. Yan, D. Polli, H. Portales, I. Arfaoui, G. Cerullo, M.P. Pileni. Nano Lett , 2013, 13, 504-508.
Supracrystals mechanical properties
Before indentation After indentation
Supracrystal of single domain nanocrystals stiffer than of polycrystalline
nanoparticles having same size (5nm)
20 nm
20 nm
20 nm
Orientational and
translational orders
translational order
polycrystals
Single domains
Hierarchical elastic properties of supracrystals
2 nm2 nm
2 μm 2 μm2 μm
2 nm
hcpb
Angle (Degree)
2nd Ring
(a) (b)
3 nm-1
Inte
nsity
1s Ring
(c)ε-Co
hcp-Co
3 nm-1
Inte
nsity
Amorphous C12 C18
E (GPa) 0.08 ± 0.03 0.7 ± 0.4
dpp (nm) 3.0 3.4M. Gauvin, N. Yang, Z. Yang, I. Arfaoui, and M. P. Pileni Nanoresearch, 2015, 8, 3480-3487
Amorphous e phase hcp
E (GPa) 0.7 ± 0.4 1.7 ± 0.5 6.6 ± 1.5
dpp (nm) 3.4 3.4 3.2
hcp
e phase
Amorphous
Amorphous e phase