NANOTECHNOLOGY • RESEARCH ON NANOCOMPOSITES
METALGRAPHITE NANOCOMPOSITE MATERIALS OF DIFFERENT
FUNCTIONAL DESTINANTION
Description
We are working out the production technologies for nanocom
posites on the base of thermoexfoliated graphite (TEG) with
the fixed transition metal (Fe, Co, Ni) particles 50100 nm in
size, which are considered to be suitable for application as
energy storage, magnetic switches, optical filters, elements of
space communication devices and catalysts of chemical reac
tions. The properties of carbon constituent (low density, resist
ance against the action of aggressive media, ecological safe
ty, high electric and heat conductivity) and peculiar character
istics of the nanoscaled metallic component are combined
harmoniously in these materials. In particular, composite
material acquires ferromagnetic properties if transition metal
nanoparticles are fixed on carbon surface.
Reasoning from the comprehensive investigation of the corre
lation between technological parameters of synthesis, struc
ture and morphology of the graphite supporter, structural
peculiarities of the metallic component and their influence on
the physical and chemical properties of the produced compos
ite materials we have created a series of the technological pro
cedures for graphitemetal NCM synthesis:
• chemical deposition from the watersalt solutions with the
subsequent salt thermolysis;
• reduction of the intercalated C8K compound by the transi
tion metal chlorides, which allows to obtain NCM with metal
situated between graphite layers in a form of atomically dis
tributed metal and on the graphite surface in a form of
nanoscaled particles;
• thermal vacuum deposition of the metals.
Graphitemetal NCMs of different functional destination have
been obtained using these procedures, for example:
• TEGFeCoCu oxide system NCM, which application as cat
alysts allowed to reduce the temperature of CO to CO2 100%
transformation down to 152oC and to increase the velocity of
oxidizing during 100% transformation at 150oC up to the val
ues of (1030)·106 mole/s·g, that is tenfold higher as com
pare to that using bulk Сu2(OH)3NO3 catalyst;
• graphiteCoFe NCMs, which application as catalysts for
the reaction of the ammonia synthesis allowed to reduce the
temperature of the reaction start (by 1000С), а also to increase
by two orders the velocity of N2 and H2 mixture transformation
into ammonia.
Now the creation of the technological procedures for production
of the nanodisperse carbon materialmetal NCMs, which will
contain carbon nanotubes, fullerens and ultradisperse natural
graphite as nanoscaled carbon constituent, is carried out.
Another direction of our activity is the creation of graphite
metal NCMs containing polymer binder that essentially
improves NCMs’ technological parameters and widens the
areas of its application. TEGpolymer and TEGmetalpolymer
application is shown to be promising for the production of pro
tective shields against electromagnetic radiation: so, for TEG
epoxy insertion attenuation (losses) at 1.8 GHz frequency was
about 25 dB.
Innovative Aspect and Main Advantages
The application of the superdisperse forms of graphite, in par
ticular, thermoexfoliated graphite, graphite films, nanotubes,
which possess highly developed surface.
150
Compacting ability of thermoexfoliated graphite allows to pro
duce bulk nanocomposite materials of the prescribed shape.
The metal or its compound deposited onto graphite is nano
crystalline (50100nm), uniformly distributed on the surface of
the disperse graphite particles and, respectively, in the bulk of
the compacted composite material.
The variation of the metallic component, its dispersity and
topology allows to obtain nanocomposite materials possess
ing peculiar physical properties, which are conditioned just by
nanodimensionality of the metal.
Deposition of the metallic component passes within the inte
grated technological cycle with disintegration of the graphite
constituent.
Our elaborations are secured by Patents of:
Device for the production of thermoexfoliated graphite (2001);
The method of the production of the metallized thermoexfoli
ated graphite (2001);
The method of the production of the catalyst for purifying tech
nological gases from carbon monoxide (2004).
Areas of Application
Catalysts for the reactions of ammonia synthesis and oxidizing
of the carbon monoxide: TEG(FeCo), TEG FeCoCu oxide
system.
Elements of the magnetic circuits: TEGCo (and CoFe com
pounds).
Magnetic switches: TEGCo (and CoFe compounds)).
Magnetic sensors: TEGСо.
Anode material for lithium ion batteries: ТEG Sn(SnSb)
Material for protective shield against electromagnetic radia
tion: TEG, TEGmetal, TEGpolymer.
а)
b)
Fig.1. Parts of TEGNi (а) and ultradisperse graphite Со (б)
powders.
Stage of Development
Technological schemes and scientifically grounded recom
mendations concerning selection of the optimum technologi
cal regimes for production of graphitemetal NCMs by different
methods.
A laboratory set of graphitemetal NCMs specimens has been
produced.
Contact Details
D.Sc. Matzui Lyudmila
Taras Shevchenko National University
01033, Kyiv33, Volodymyrska st., 64,
Ukraine
Phone: +380445262384
Email: matzui@univ.kiev.ua