Catalytic Surface Specificity of Ni(OH)2 -Decorated Pt Nanocubes for the Hydrogen Evolution Reaction in an Alkaline Electrolyte

Youngmin Hong; Chang Hyuck Choi; Sang-Il Choi

doi:10.1002/cssc.201901539

Catalytic Surface Specificity of Ni(OH)₂ -Decorated Pt Nanocubes for the Hydrogen Evolution Reaction in an Alkaline Electrolyte

ChemSusChem. 2019 Sep 6;12(17):4021-4028. doi: 10.1002/cssc.201901539. Epub 2019 Aug 13.

Authors

Youngmin Hong¹, Chang Hyuck Choi², Sang-Il Choi¹

Affiliations

¹ Department of Chemistry and Green-Nano Materials Research Center, Kyungpook National University, Daegu, 41566, Korea.
² School of Materials Science and Engineering, Gwangju Institute of Science and Technology, Gwangju, 61005, Korea.

PMID: 31286683
DOI: 10.1002/cssc.201901539

Abstract

Because the hydrogen evolution reaction (HER) in alkaline electrolyzers is initiated by water dissociation, the hydrogen evolution kinetics are sluggish even on highly active Pt catalysts. Here, we have synthesized Ni(OH)₂ -decorated Pt nanocubes as a bifunctional catalyst to enhance the HER kinetics in an alkaline medium. Electrochemical cyclic voltammetry and CO-stripping measurements confirmed the selective deposition of Ni(OH)₂ on the Pt(1 0 0) facets of nanocubes. Electrocatalytic HER activity of the Ni(OH)₂ -decorated Pt nanocubes demonstrated that the bifunctional catalytic surface promotes the Volmer step kinetics and thus the Volmer/Tafel coupling dominant. As the result, catalytic surface specificity of Ni(OH)₂ -decorated Pt nanocubes enhanced water dissociation, reduced contamination of OH_ad on Pt surface, and maintained long-term HER performance in alkaline electrolytes.

Keywords: alkaline; bifunctional catalyst; hydrogen evolution; nickel hydroxide; platinum.