Слайд 1 - PCAM - Physics and Chemistry of Advanced Materials

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Lomonosov Moscow State
University
Actual topics for collaboration on Physics
and Chemistry of Advanced Materials
Topics:
Advanced carbon materials for modern applications
Professor A. Obraztsov, Physics Department
Materials for energy storage and conversion
Professor E. Antipov, Chemistry Department
Organic photovoltaics
Professor D.Paraschuk, Physics Department
New technology of HT-supercondactors production
Professor A. Kaul, Chemistry Department
Novel thermoelectric materials
Professor A.Shevelkov, Chemistry Department
Others topics could be considered as well!
Lomonosov Moscow State University
Actual topics for PCAM collaboration
Carbon nanotube forest production by CVD
cathode
plasma
Metal plate with holes
substrate
anode
Remote plasma allows usage non-conductive (dielectric) materials for substrate and
reduce substrate temperature.
Lomonosov Moscow State University
Actual topics for PCAM collaboration
[R.R. Ismagilov et al., Nano ACS, submitted]
Non-catalytical production of carbon nanotubes
Traditional catalytical CNT growth
“Catalyst free” growth of CNT
Lomonosov Moscow State University
Actual topics for PCAM collaboration
[R.R. Ismagilov et al., Nano ACS, submitted]
Mesoporous Nano-Graphite Films
A.N. Obraztsov et al.,
Diamond and Rel. Mat. 8(199)814
Carbon 46(2008)963
Lomonosov Moscow State University
Actual topics for PCAM collaboration
Graphite films of nanometer thickness
AFM image of
graphite film on Ni
STM image of
graphite film on Ni
Graphite CVD films on Ni
contain atomically flat regions
and net of wrinkles. Typical
height of the wrinkles is about
30 nm.
Lomonosov Moscow State University
Actual topics for PCAM collaboration
[A.N. Obraztsov et al., Carbon 45(2007)2017]
Field Effect Transistor of CVD Graphite Film
FET device made with
graphene flakes pilled out
from CVD graphite film.
19
2
2
m o b ( h o le ) = 2 8 3 0 c m /V * s e c
2
m o b ( e le ct r o n ) = 2 1 8 0 c m /V * s e c
6 p ro b e s
h o le
1 ,0 x 1 0
3,5*10
e le ct r o n 2 , 7 * 1 0
Conductanc e, S
1 ,5 x 1 0
-5
8
-5
-5
3
4 p ro b e s
h o le
1,3*10
e le ct r o n 1 0
-5
-5
4
-5
V tg , V
- 2,0
- 1,8
- 1,6
Lomonosov Moscow State University
Actual topics for PCAM collaboration
- 1,4
4 and 6 probe measurement at Room temperature
SiO2 – bottom gate (15)
Al2O3 – top gate (2)
Source-drain contact (3,4,8,19): 5 nm Ti & 50 nm Au
New materials for Li batteries
Li batteries – the most efficient energy
storage devices
Design and testing of new cathode
materials based on mixed transition metal
compounds with polyanions:
fluorophosphates and borates
Motivation:
1)higher ionicity of the M-F bond (as compared to the M-O one) and “inductive effect” of the (MOn)mpolyanions with strong M-O bonds is expected to enhance the potential of the corresponding Mn/Mn+1 redox
couple
2)twice larger amount of F is needed to achieve the same valence for transition metal  larger free unit cell
volume  faster lithium migration
Materials for batteries with higher energy and power densities
Lomonosov Moscow State University
Actual topics for PCAM collaboration
Li2CoPO4F: perspective high-voltage cathode material
- Li1
- Li2
- Li3
a
a
b
c
c
b
2 migration pathways
 + 3.5% volume expansion (0.6 Li removal)
in contrast to 7% volume contraction in olivine
“Solid solution” behavior
Upper limit of electrolyte
Capacity vs. voltage: from potentiostatic step
measurements between 4.2 V and variable
anodic potentials.
The slope of the capacity-voltage dependence 0.7 V per 1Li mole (like in LiCoO2)
High potential range
Cathode material for high energy and
power densities batteries
Lomonosov Moscow State University
Actual topics for PCAM collaboration
1) Patent: “New Alkali Transition Metal Fluorophosphate”
International Publication Number WO 2010/023129 A2, 2010,
2) Structural transformation of Li2CoPO4F upon Li-deintercalation /
JOURNAL OF POWER SOURCES 196 (2011) 355-360
Third generation organic and hybrid photovoltaics:
thin, flexible, cheap, and efficient
Polymer-fullerene bulk heterojunction solar cells
Electrodes
Fullerene
Polymer
Flexible substrate
Protective layer
Light
100 nm
Lomonosov Moscow State University
Actual topics for PCAM collaboration
Active area 13 mm2
Efficiency 4% @ AM1.5
Active area ~1 cm2
Efficiency ~1% @ AM1.5
Novel nanomaterials for third generation photovoltaics
The goals: - towards 10% efficiency
- to scale by wet roll-to-roll technology
• Donor-acceptor charge-transfer complexes of conjugated polymers, highly
photostable
• Exohedral metallocomplexes of fullerenes
for higher photovoltage
• Low-bandgap polymers for
higher photocurrent
•
For dye-sensitized solar cells: low-temperature TiO2 processing, Ru-free dyes,
soft-solid electrolyte
Lomonosov Moscow State University
Actual topics for PCAM collaboration
Second generation (2G) HTSC coated conductor architecture
The technology is based on
Metalorganic Chemical Vapor
Deposition (MOCVD) of buffer
and superconducting layers.
1. Biaxially textured metal tape obtained by cold rolling & annealing
2. Oxide buffer layer epitaxially grown on textured tape
3. Epitaxial superconducting layer of YBa2Cu3O7-δ
4. Protecting layer of normal metals ( Ag + Cu)
- high deposition rate
~100 μm
~ 1 μm
The realized conception of the material is based on
the texture transfer from metal tape (textured
substrate) to superconducting layer via the buffer
layer
Lomonosov Moscow State University
Actual topics for PCAM collaboration
- high superconducting
properties of HTSC layers
- easy way to introduce
nanosized inclusions for
increasing superconducting
current in high external
magnetic field
- low process price compared to
high vacuum deposition
technologies
At home synthesized
volatile precursors
Home made МОСVD
equipment
-Non-toxic
-May be produced in industrial
scale at moderate price
Me(thd)3
Lomonosov Moscow State University
Actual topics for PCAM collaboration
New Ideas for Better TE Materials
Modern concept: Phonon Glass, Electron Crystal (PGEC)
Basic idea:
Almost independent optimization of charge carrier transport and phonon transport
due to the spatial separation of structural elements
Phonon engineering !
New objects
1. Nanocage and nanoblock compounds
2. Nanocomposites
3. Superlattices and Nanostructures
2
Lomonosov Moscow State University
Actual topics for PCAM collaboration
1
A.V. Shevelkov, Russ. Chem. Rev. 2008, 77, 1–19
A.V. Shevelkov, et al. Chem. Mater. 2008, 20, 2476–2483
A.V. Shevelkov, et al. Inorg. Chem. 2009, 48, 3720–3730
Recent Achievements in TE Engineering
Nanocage inorganic clathrates
Covalent framework: efficient transport of charge carriers
Guest “rattling”: rejection of heat-carrying phonons
High thermoelectric efficiency
ZT = S2T/
(dimensionless)
Prove of the concept:
Extremely low thermal conductivity:
lowest for narrow-gap semiconductors
1.
2.
Already promising properties:
ZT0.6 at 650 K  for automotive applications
ZT0.4 at 1100 K coupled to utmost chemical and thermal stability 
for solar energy conversion
3.
Almost 3-time growth of ZT at 300 K with nanocomposites formation  are new
routes to better ZT possible?
Lomonosov Moscow State University
Actual topics for PCAM collaboration
A.V. Shevelkov, et al. Solid State Sci. 2007, 9, 664–671
A.V. Shevelkov, et al. Chem. Eur. J. 2008, 14, 5414–5422.
A.V. Shevelkov, et al. Chem. Eur. J. 2010, 16, 12582–12589
PCAM-MSU:
Looking forward for fruitful collaboration!
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