Facile electrodeposition of three-dimensional flower-like structure of nickel matrix composite electrodes for hydrogen evolution reaction

Abstract

Two kinds of three-dimensional flower-like structure of nickel matrix composite electrodes with activated carbon (AC) or 50 nm carbon (C) particles have been successfully synthesized by a facile one-step composite electrodeposition process in a deep eutectic solvent (DES). The effects of different carbon materials and concentrations on the morphology and composition of composite coatings were systematically investigated. The formation mechanism of the composite coatings was proposed. The electro-catalytic activity of the deposited Ni matrix composite coatings containing AC or 50 nm C particles for hydrogen evolution reaction (HER) was also evaluated and compared. The results implied that the Ni matrix composite coatings incorporating with either AC or 50 nm C particles exhibited improved active surface area and higher catalytic activity for HER. Briefly, the overpotential can reach a value of 114 mV at the current density of 10 mA cm−2 in 1 M KOH, with the Tafel slope reaching 73.8 mV dec−1. This work provides a promising electrolyte and a facile strategy to design and prepare non-noble metal materials in catalysis field.