3D nanostructured NiMo catalyst electrodeposited on 316L stainless steel for hydrogen generation in industrial applications

Abstract

Nowadays, massive NiMo alloys are considered highly active catalysts for the hydrogen evolution reaction (HER) in industrial alkaline electrolysers. Thus, it is desirable to study other alternative materials, preserving the specific properties of these alloys. In this study, a NiMo coating on 316L stainless steel with high resistance to the corrosive medium is obtained by electrodeposition process. Properties and structural characteristics of the new synthesized material have been correlated with its efficiency as electrocatalyst. In this study, using a simple plating method, it was possible to obtain a material with a catalytic activity for the HER in alkaline media, which is 37.6 times higher than that of conventional raw Ni catalysts, at a considerably lower cost. The 3D nanostructured NiMo catalyst synthesized presented a highly roughened surface with porous microstructure, which is an essential requirement for obtaining high catalytic activity with this type of systems. The porous microstructure in the coating has been confirmed by X ray diffraction and scanning electron microscopy. Raman spectra of the surface evidenced the formation of superficial species before and after the ageing treatment by prolonged chronoamperometry in alkaline electrolyte. This feature was also confirmed by the analysis of X ray photoelectron spectroscopy measurements.