FUNCTIONAL COMPOSITION AND ELECTROCHEMICAL CHARACTERISTICS OF OXIDIZED NANODISPERSE CARBON
K.M. Popov1, Yu.V. Fedoseeva1,2, O.A. Kokhanovskaya3, G.I. Razd`yakonova3, D.A. Smirnov4, L.G. Bulusheva1,2, A.V. Okotrub1,2
1Nikolaev Institute of Inorganic Chemistry, Siberian Branch, Russian Academy of Sciences, Novosibirsk, Russia 2Novosibirsk National Research State University, Novosibirsk, Russia 3Institute of Problems of Hydrocarbon Processing, Siberian Branch, Russian Academy of Sciences, Omsk, Russia 4Institute of Solid State Physics, Dresden, Germany
Keywords: нанодисперсный углерод, окисление, функциональный состав, РФЭС, NEXAFS, электрохимические процессы, циклическая вольамперометрия, суперконденсаторы, долговременное циклирование, nanodisperse carbon, oxidation, functional composition, XPS, electrochemical processes, cyclic voltammetry, supercondensors, long-term cycling
Abstract
The functional composition and electrochemical behavior of the samples of N121 oxidized nanodisperse technical carbon in aqueous electrolytes are studied. For oxidation 30% aqueous hydrogen peroxide (H2O2) solution and 2% H2O2 with the addition of singlet oxygen or ozone were used. By means of X-ray photoelectron spectroscopy data and the analysis of the near edge X-ray absorption fine structure the features of the chemical structure of the samples are found. The oxygen concentration did not exceed 5 at.% in the samples. The analysis of cyclic voltammograms reveals that at low potential sweep rates the specific capacity of the material is determined by the functional composition of the surface. The sample oxidized by 30% H2O2 solution and containing the largest number of -OH and -COOH groups demonstrated the highest capacity in 6M KOH and in 1М H2SO4 it was the sample with the highest concentration of C=O groups formed during the oxidation with singlet oxygen. The stability of carbon electrodes is studied in supercondensor models.
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