Abstract
The anodic oxidation of 3000°C annealed pyrolytic graphite electrode was studied by the technique of potential sweep at linearly changing from 0.00V to+1.50V vs PHE, and by measuring the change of (00l) X-ray diffraction patterns, in 10M/l sulfuric acid electrolyte at 25°C.
Experimental results are summerized as follows:
(1) On the anodic potential sweep curves, two oxidation current peaks are observed as a small peak at about+1.2V and major current beyond+1.3V. The for, mer peak corresponds to the adsorption of oxygen on graphite surface and the latter to formation of graphite bisulfate lamellar compound prior to oxygen evolution.
(2) On the cathodic sweep curves, the reduction current that appears as a peak between+1.30V and+1.00V corresponds to the decomposition of lamellar compound.
