Hydrogen evolution on Au/GC and PdAu/GC nanostructures in acid solution: AFM, XPS, and electrochemical study

Abstract

HER was examined on various glassy carbon-supported Au and PdAu electrodes in acid solution. The Au/GC electrodes were obtained after Au was electrodeposited on a GC substrate by holding the potential for various times in 0.5 M H2SO4 solution containing AuCl4− ions. PdAu/GC electrodes were obtained after Pd has been added by a spontaneous deposition on previously prepared Au/GC electrodes. Surface morphology and chemical analysis of Au/GC and PdAu/GC electrodes were performed by atomic force microscopy and X-ray photoemission spectroscopy. Electrochemical characterization was performed by cyclic voltammetry in 0.5 M H2SO4 solution, while the linear sweep voltammetry was used to gain insight into the electrocatalytic activity of these electrodes for HER. 30minPd/10minAu/GC electrode consisting of 48% Pd and 65% Au, with the total coverage of the GC substrate with PdAu islands of 70%, showed the best catalytic activity for HER. A remarkable high activity and stability of this electrode makes it a promising catalyst for HER in acid solution.