Conference paper

Hydrogen Evolution on Pyrolytic Graphite

A. R. Despić ; Faculty of Technology and Metallurgy, University of Belgrade
D. M. Dražić ; Faculty of Technology and Metallurgy, University of Belgrade
G. A. Savić-Maglić ; Faculty of Technology and Metallurgy, University of Belgrade
R. T. Atanasoski ; Faculty of Technology and Metallurgy, University of Belgrade

Abstract

The hydrogen evolution reaction from acid solutions was
studied on highly oriented pyrolytic graphite at different surfaces
obtained by cutting graphite under the various angles in respect
to the basal plane. The experiments were done galvanostatically
on the polished samples of desired orientation, in a cell which
enabled the pretreatment of graphite at 1000° C in argon and use
of prepurified Na2S04 + H2S04 solutions.
Tafel lines with 2 RT/F slopes were obtained in all the
experiments with i 0 varying from ca 10-9A/cm2 for cleavage
plane to ca 10-8A/cm~ for edge plane. The transients show the
considerable pseudo-capacitances of 250--500 μF/cm2 being larger
at more negative potentials and edge surfaces.
The experimental data are consistent with the slow discharge
- electrochemical desorption mechanism with the limited number
of sites of H adsorption but also with the coupled discharge -
recombination reaction for hydrogen evolution.

Keywords

Hrčak ID:

197288

URI

https://hrcak.srce.hr/197288

Publication date:

15.5.1972.

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