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Lomonosov Moscow State University
Actual topics for collaboration on Physics and Chemistry of Advanced Materials
Lomonosov Moscow State UniversityActual topics for PCAM collaboration
Topics:
Advanced carbon materials for modern applicationsProfessor A. Obraztsov, Physics Department
Materials for energy storage and conversionProfessor E. Antipov, Chemistry Department
Organic photovoltaicsProfessor D.Paraschuk, Physics Department
New technology of HT-supercondactors productionProfessor A. Kaul, Chemistry Department
Novel thermoelectric materialsProfessor A.Shevelkov, Chemistry Department
Others topics could be considered as well!
Metal plate with holes
substrate
anode
plasmacathode
Carbon nanotube forest production by CVDCarbon nanotube forest production by CVD
Remote plasma allows usage non-conductive (dielectric) materials for substrate and reduce substrate temperature.
[R.R. Ismagilov et al., Nano ACS, submitted]Lomonosov Moscow State UniversityActual topics for PCAM collaboration
Non-catalytical production of carbon nanotubesNon-catalytical production of carbon nanotubes
Traditional catalytical CNT growthTraditional catalytical CNT growth
““Catalyst free” growth of CNTCatalyst free” growth of CNT
[R.R. Ismagilov et al., Nano ACS, submitted]Lomonosov Moscow State UniversityActual topics for PCAM collaboration
Mesoporous Nano-Graphite FilmsMesoporous Nano-Graphite Films
A.N. Obraztsov et al.,Diamond and Rel. Mat. 8(199)814Carbon 46(2008)963
Lomonosov Moscow State UniversityActual topics for PCAM collaboration
AFM 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.
Graphite films of nanometer thicknessGraphite films of nanometer thickness
STM image of graphite film on Ni
[A.N. Obraztsov et al., Carbon 45(2007)2017]Lomonosov Moscow State UniversityActual topics for PCAM collaboration
Field Effect Transistor of CVD Graphite FilmField Effect Transistor of CVD Graphite Film
19
8
2
3
4
FET device made with graphene flakes pilled out from CVD graphite film.
-2,0 -1,8 -1,6 -1,4
1,0x10-5
1,5x10-5
mob(hole)=2830 cm2/V*sec
mob(electron)=2180cm2/V*sec
6 probes
hole 3,5*10-5
electron 2,7*10-5
4 probes
hole 1,3*10-5
electron 10 -5
Vtg, V
Co
nd
uct
anc
e, S
4 and 6 probe measurement at Room temperatureSiO2 – bottom gate (15)Al2O3 – top gate (2)Source-drain contact (3,4,8,19): 5 nm Ti & 50 nm Au
Lomonosov Moscow State UniversityActual topics for PCAM collaboration
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)m- polyanions 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 UniversityActual topics for PCAM collaboration
LiLi22CoPOCoPO44F: perspective high-voltage cathode materialF: perspective high-voltage cathode material
a
cb
a
bc
- Li1 - Li2 - Li3
2 migration pathways
Capacity vs. voltage: from potentiostatic stepmeasurements between 4.2 V and variable anodic potentials.
Upper limit of electrolyte
The slope of the capacity-voltage dependence 0.7 V per 1Li mole (like in LiCoO2)
+ 3.5% volume expansion (0.6 Li removal)in contrast to 7% volume contraction in olivine
“Solid solution” behavior
High potential range
Cathode material for high energy and power densities batteries
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
Lomonosov Moscow State UniversityActual topics for PCAM collaboration
Third generation organic and hybrid photovoltaics:thin, flexible, cheap, and efficient
Electrodes Fullerene
Flexible substrate Protective layer
Polymer Light
Polymer-fullerene bulk heterojunction solar cells
100 nm
Active area 13 mm2 Efficiency 4% @ AM1.5 Active area ~1 cm2
Efficiency ~1% @ AM1.5Lomonosov Moscow State UniversityActual topics for PCAM collaboration
Novel nanomaterials for third generation photovoltaics
• 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
The goals: - towards 10% efficiency - to scale by wet roll-to-roll technology
Lomonosov Moscow State UniversityActual topics for PCAM collaboration
Second generation (2G) HTSC coated conductor architecture
1. Biaxially textured metal tape obtained by cold rolling & annealing2. Oxide buffer layer epitaxially grown on textured tape
3. Epitaxial superconducting layer of YBa2Cu3O7-δ
4. Protecting layer of normal metals ( Ag + Cu)
~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
The technology is based on Metalorganic Chemical Vapor Deposition (MOCVD) of buffer and superconducting layers. - high deposition rate
- 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
Lomonosov Moscow State UniversityActual topics for PCAM collaboration
Home made МОСVD equipment
At home synthesized volatile precursors
-Non-toxic
-May be produced in industrial scale at moderate price
Me(thd)3
Lomonosov Moscow State UniversityActual topics for PCAM collaboration
Modern concept: Phonon Glass, Electron Crystal (PGEC)
New Ideas for Better TE Materials
Basic idea: Almost independent optimization of charge carrier transport and phonon
transport due to the spatial separation of structural elements
Phonon engineering !
New objects1. Nanocage and nanoblock compounds 2. Nanocomposites3. Superlattices and Nanostructures
1
2 A.V. Shevelkov, Russ. Chem. Rev. 2008, 77, 1–19A.V. Shevelkov, et al. Chem. Mater. 2008, 20, 2476–2483 A.V. Shevelkov, et al. Inorg. Chem. 2009, 48, 3720–3730
Lomonosov Moscow State UniversityActual topics for PCAM collaboration
Prove of the concept:Extremely low thermal conductivity:
lowest for narrow-gap semiconductors
Recent Achievements in TE EngineeringNanocage inorganic clathrates
Covalent framework: efficient transport of charge carriers Guest “rattling”: rejection of heat-carrying phonons
High thermoelectric efficiencyZT = S2T/
(dimensionless)
Already promising properties: 1. ZT0.6 at 650 K for automotive applications2. ZT0.4 at 1100 K coupled to utmost chemical and thermal stability for
solar energy conversion3. Almost 3-time growth of ZT at 300 K with nanocomposites formation are new
routes to better ZT possible?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
Lomonosov Moscow State UniversityActual topics for PCAM collaboration
PCAM-MSU:Looking forward for fruitful collaboration!