ISSN 1070-4272, Russian Journal of Applied Chemistry, 2007, Vol. 80, No. 2, pp. 285!289. + Pleiades Publishing, Ltd., 2007.
Original Russian Text + I.A. Bashmakov, V.A. Dorosinets, V.K. Ksenevich, A.A. Mel’nikov, F.N. Kaputskii, 2007, published in Zhurnal Prikladnoi Khimii,
2007, Vol. 80, No. 2, pp. 286 !290.
NANOTECHNOLOGY AND NANOMATERIALS
Formation of Thin Carbon Films Containing Metal
Nanoparticles by Thermolysis of a Polymer Precursor
I. A. Bashmakov, V. A. Dorosinets, V. K. Ksenevich,
A. A. Mel’nikov, and F. N. Kaputskii
Research Institute of Physicochemical Problems, Belarussian State University, Minsk, Belarus
Belarussaian State University, Minsk, Belarus
Received June 29, 2006
Abstract-A new procedure was developed for preparing carbon films with magnetic metal nanoparticles
by thermolysis of a polymer precursor. The conditions for preparing carbon films with required surface con-
centration of the metal nanoparticles and hence with dielectric or metallic properties were determined.
The unabated interest in nanoheterogeneous struc-
tures consisting of a matrix and metal nanoparticles as
a filler is caused by their unusual dielectric, magnetic,
chemical, and biological properties [1, 2], which, in
turn, are due to the size effects. The properties of
these composites can be changed by using an insulat-
ing or conducting matrix with different concentrations
of metal nanoparticles.
Nanoheterogeneous systems are characterized by
interesting mechanisms of charge transport, in partic-
ular, quantum corrections to the conductivity [3, 4]
and tunnel effects and giant magnetoresistance [5, 6].
The materials can be used in practice for production
of gas sensors, magnetic field transducers, magnetic
memory units with superhigh packing density of
the components, etc. [7, 8]. Metal nanoparticles are
widely used as catalysts not only for conventional
reactions but also for growth of carbon nanotubes
[9, 10] and onion-like structures .
Films and, especially, thin films occupy a promi-
nent place among composites containing metal nano-
particles. The properties of these films are determined
mainly by the properties and transformations of their
surface. Carbon films containing metal nanoparticles
are promising materials for micro- and nanoelectronics.
One of the procedures for preparing carbon films
containing metal nanoparticles is thermolysis of met-
al-containing polymer precursors [12, 13]. The con-
ductivity of films prepared by this method can be
varied in a wide range (from dielectric to metal) by
changing the thermolysis temperature. However, it
is difficult to prepare monodisperse metal particles
by this method (especially at high annealing temper-
atures) and to control the content of metal nanopar-
ticles in the carbon matrix.
The aim of this study was to prepare dielectric and
conducting thin carbon films with a required content
of magnetic metal nanoparticles from a polymer pre-
The procedure for preparing carbon films with
required content of metal nanoparticles consists of
The fist step involves preparation of thin polymer
films, introduction of an appropriate transition metal
ion (e.g., Co
, etc.) into the film, and ther-
molysis of the polymer precursor. The second step is
treatment of the metal-carbon film with an aqueous
solution of palladium chloride. The third (final) step
is treatment of the film containing palladium nano-
particles with a nickel-plating solution.
The first step can be conventionally subdivided
in three steps: (I31) preparation of thin polymer films,
(I32) introduction of inorganic cations into the films,
and (I33) thermolysis of metal salts of the polymer
in a vacuum.
We used starch as an initial polymer. Starch mac-
romolecules were modified with nitro ester and car-
boxy groups . The modified starch is soluble
in ethers, esters, and alcohol-ether mixtures. Because
the coefficient of spreading of a polymer solution over
the water surface is positive  (S > 0 is the neces-