Nanoporous Gold Surface: An Efficient Platform for Hydrogen Evolution Reaction at Very Low Overpotential

Author(s)

Sukeri, Anandhakumar ^[1] ; Bertotti, Mauro ^[1]

Affiliation

^[1] Univ Sao Paulo, Inst Quim, Dept Quim Fundamental, Av Prof Lineu Prestes 748, BR-05513970 Sao Paulo, SP - Brazil

• Document type: Journal article
• Source: Journal of the Brazilian Chemical Society; v. 29, n. 2, p. 226-231, FEB 2018.
• Web of Science Citations: 4

Abstract

A nanostructured porous gold film (NPGF) was fabricated onto a gold electrode surface by an electrochemical approach involving anodization followed by electrochemical reduction in absence of binary alloys, templates and chemical reducing agents. The electrocatalytic activity of the as-fabricated electrocatalyst was examined towards hydrogen evolution reaction (HER) and very low onset potential (-0.048 V) and overpotential values of -0.070 and -0.083 V at current densities of 10 and 20 mA cm(-2), respectively, were obtained in 0.5 mol L-1 sulfuric acid solution, along with exchange current density (j(o)) of 0.126 mA cm(-2). A small Tafel slope of ca. 36 mV decade(-1) was achieved, indicating the HER takes place according to a Volmer-Heyrovsky mechanism and that the electrochemical desorption of hydrogen is the rate determining step. The performance of the NPGF electrode was compared with that of bulk gold and platinum electrodes, and a platinum-like behavior was noticed for HER. Finally, the durability of the proposed electrocatalyst was examined using voltammetric and amperometric techniques and an excellent stability was achieved. (AU)

• FAPESP's process: 14/15215-5 - Fabrication and characterization of nanoelectrodes for use in Scanning Electrochemical Microscopy (SECM): fundamental and analytical applications
• Grantee: Sukeri Anandhakumar
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• FAPESP's process: 15/20776-9 - Fabrication of nanometric probes for the study of biochemical processes by using Scanning Electrochemical Microscopy
• Grantee: Mauro Bertotti
• Support Opportunities: Regular Research Grants