ISSN 1070-4272, Russian Journal of Applied Chemistry, 2014, Vol. 87, No. 10, pp. 1517−1523. © Pleiades Publishing, Ltd., 2014.
Original Russian Text © Yu.A. Kukushkina, V.V. Sokolov, M.V. Tomkovich, 2014, published in Zhurnal Prikladnoi Khimii, 2014, Vol. 87, No. 10, pp. 1466−1473.
Nanoporous Carbon Prepared by Thermochemical
Treatment of Carbide with Chlorine
Yu. A. Kukushkina, V. V. Sokolov, and M. V. Tomkovich
Ioffe Physicotechnical Institute, Russian Academy of Sciences, ul. Politekhnicheskaya 26, St. Petersburg, 194021 Russia
Received November 13, 2014
Abstract—The inﬂ uence exerted by the chemical composition of В, Si, Ti, Zr, Hf, V, Nb, Ta, Mo, and Cr car-
bides and by the temperature of their chlorination on the ordering in the arrangement of carbon layers forming
the structure of nanoporouos carbon was demonstrated. The pore structure characteristics of the materials were
studied in relation to the composition of the starting carbides and to the chlorination conditions. The speciﬁ c
surface area of the carbon materials, as a rule, drastically decreases as the chlorination temperature is increased
Steady interest in nanoporous carbon (carbide-
derived carbon, CDC) prepared by thermochemical
treatment of carbides with chlorine is due to prospects
for its use as cathode material for supercapacitors, as
sorbent, as catalyst support, as precursor for preparing
nanocomposites, etc. [1–7].
Some speciﬁ c features of the CDC technology and
properties are given in reviews [5, 6].
The necessary conditions for preparing CDC by
chlorination of carbides is minimal volume shrinkage of
carbide particles and high volatility of the chlorides formed
(low boiling or sublimation point). The chlorination
temperature should be higher than the boiling point of the
chloride. Otherwise, a shielding ﬁ lm of solid or molten
chloride, preventing further chlorination, can be formed.
The majority of chlorides have the boiling or
sublimation point no higher than 350°С. The exceptions
are Fe, Cr, Mg, and Ca chlorides, whose boiling points
are 1026, 947, 1412, and 1627°С, respectively .
The parameters of the pore structure (speciﬁ c surface
area, pore size, speciﬁ c pore volume) of the forming CDC
(at negligible volume shrinkage caused by self-organization
of the carbon atoms released upon cleavage of М–С bonds)
are determined by the content of the carbide-forming ele-
ment in the carbide, by its atomic size, and by the density
of atom packing in crystalline carbides .
Among numerous carbides, the B, Si, and Ti carbides
are of most interest as raw materials from the practical
viewpoint because of high carbon content (21, 30,
and 20 wt %, respectively) and low boiling points of
the chlorides (13, 57, and 136°С, respectively ).
Furthermore, powders of B, Si, and Ti carbides are
commercially available with a wide granule size spectrum.
In CDC preparation, the metal carbides used are
simultaneously raw materials for preparing Ti and
Zr chlorides, e.g., by chlorination in fluidized-bed
apparatuses . Fluidized-bed apparatuses exhibit
high productive capacity due to efﬁ ciency of the mass
and heat exchange. They allow implementation of an
integrated waste-free technology with simultaneous
production of CDC and metal chlorides, which makes
the CDC production process still more promising from
the economical viewpoint.
In the end of the XX century, a research team of the
Leningrad Institute of Technology under the guidance of
N.F. Fedorov systematically studied the chlorination of a
wide range of carbides (B
C, SiC, TiC, ZrC, UC, NbC,
C, TaC, WC, VC) . Since 2000, studies in this ﬁ eld
are also performed under the guidance of Yu.G. Gogotsi.
In these studies, CDC samples based on Ti, Si, Nb, V, B,
Fe, and Zr carbides were prepared, and their pore structure
was examined [6, 11].