II International Symposium on Carbon for Catalysis ABSTRACTS

PP-I-26
Pt-NANOCLUSTERS SUPPORTED ON CARBON NANOMATERIALS
Kuyunko N.S., Kushch S.D., Muradyan V.E., Volodin A.A., Tarasov B.P.
Institute of Problems of Chemical Physics RAS, Chernogolvka, Russia
e-mail: ksd@icp.ac.ru
Carbon nanomaterials (CNM) are considered as convenient supports for metals
nanoclusters because of developed surface, electroconductivity and ability to electrons
transfer. Both these properties and synthesis methods readiness in grams scale allow to
consider features of platinum nanoclusters fixation onto CNM and show advantages of these
materials as a catalysts for redox processes in the present paper.
Products of electroarc graphite evaporation such as X-ray amorphous carbon (AC) after
fullerenes extraction, multi-walled carbon nanotubes (MWNT) from cathode deposit spongy
part, wherein a graphite rods diameters are 10 mm, current intensity is 100 A, He pressure is
500 Torr and the yields in optimal conditions are 15 and 90 % per evaporated graphite
weight; single-walled nanotubes (SWNT) with yield of 10 % per composite of graphite with
Ni-Y catalyst weight and carbon nanofibers (CNF) as product of pyrolysis of
С 2 Н 4 /Н 2 /Ar = 30:52:18 % vol. mixtures at 550°C over LaNi 5 are used as catalysts supports.
АС and MWNT with specific surface areas 287 and 25 m 2 g -1 are used without
purification . SWNT is purified from AC and catalysts impurities by an alternative stages of
HCl conc. treatment and step-like air oxidation (from 300 to 550ºС), that allows to assume of
SWNT content about 80 % and specific surface area to 380 m 2 g -1 . CNF were purified from
catalysts impurities by ultrasonic cleaning in HCl conc. during 3 h and sample with trace
metal content and specific surface area to 58 m 2 g -1 is obtained. Used CNM appreciably are
differ in a structure and in a reactivity (for example in the air thermogravimetry, fig. 1). So,
SWNT, MWNT and CNF include plane or convolute graphene letters in the main but AC
contains an alternate unconjugated single and double bonds in five- and six-member rings.
SWNT, MWNT and CNF are oxidized by HNO 3 conc. at 70ºС for “anchor” groups
introduction. АС is used without pretreatment or brominated with following alkaline
saponification. Both Br- and hydroxyl-derivatives of AC with the gross-formula С 10 (ОН)
formation are shown by IR-spectroscopy and elemental analysis. These treatment methods
allow to increase oxygen-containing groups content in the samples that these groups does not
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