Anodically Pretreated Carbon Electrode Surfaces and Their Effects on the Electrode Reaction

Abstract

Pretreatment of carbon electrodes through anodic oxidation resulted in enhancement of the oxidation peak of chlorpromazine (CPZ) on its cyclic voltammogram. The glassy carbon (GC)electrodes treated in phosphate, arsenate, tartrate, and citrate solutions exhibited especially marked enhancement. The peak current of CPZ was appreciably affected by the experimental conditions at pretreatment such as electrolyte, pH, and electrolysis potential and time. From ESCA and IR spectral observations and colorimetric analysis of the suspension of GC particles obtained from the electrode surface, modification of the electrode surface by formation of some species arising from such electrolyte anions was noticed. The newly formed species on the electrode surface are supposed to exert their activation effect on the oxidation of CPZ. These species are considered to function for accumulating CPZ by adsorption and for promoting the oxidation of CPZ with their catalytic action. The structural contribution of these anions to the effect was discussed.