A Loss of Charge at Reduction of Hydrogen Ion by Fast Scan Voltammetry

Abstract

The voltammetry of hydrogen ion is revisited quantitatively at a thin wire platinum electrode at scan rates less than 8 V s−1 in the context of the amount of adsorption and the negative capacitance. The first reduction wave was attributed to the reduction of adsorbed hydrogen ion, which is inconsistent with the Volmer step. The second one was composed of the partially-diffusion control current and the negatively capacitive current associated with the redox reaction. The capacitance causes the potential shift at high scan rates owing to the relaxation of the electric field for the faradaic reactions.