Electrocatalytic reduction of dioxygen at cetyltrimethylammonium bromide modified carbon paste electrode

A cetyltrimethylammonium bromide modified carbon paste electrode (CTAB/CPE) was developed. The modification was based on the hydrophobic adsorption of CTAB on the surface of CPE. This electrode exhibited excellent catalytic activity toward the reduction of dioxygen (O-2). Compared with the poor signals at bare CPE, O-2 had much larger reduction current and more positive peak potential at CTAB/CPE, which may arise from the formation of a positively charged layer of CTAB on the surface of CPE. The effects of some parameters on the O-2 reduction were examined, including electrolyte pH, amount of modifier, scan rate and composition of carbon paste. The preparation of this electrode not only produced a new chemically modified carbon paste electrode but also provided a useful sensor for the determination of O-2.