Effect of Lithium Sulfate on the Catalytic Activity of Pt for Hydrogen Oxidation Reaction

Abstract

The effect of Lithium sulfate on the hydrogen oxidation reaction (HOR) in 0.1 M H2SO4 electrolyte was investigated on flat Pt electrode. The Li+ concentration solutions of 0, 10, 25 and 32 g l−1 were studied using cyclic voltammetry and rotating disk electrode (RDE) techniques. The obtained results demonstrate a good repeatability and confidence in analysis method, to understand the influence of lithium sulfate on HOR for an electrocatalysis system. The electrochemical surface area, limiting current and kinetic parameters were measured and analysed using Koutecky-Levich and Tafel representations to investigates the different types of lithium sulfate interactions on the catalytic properties of Pt. In presence of Li2SO4, the H+ adsorption/desorption process, species mass-transport and kinetic current density are reduced. Furthermore, the Tafel’s slope analyse show a change of the rate-determining steps for HOR mechanism. More detailed results of the kinetic analysis and lithium impact on the studied systems are discussed in this work.