Interfacial engineering of Ni–Co–Mn@Ni nanosheet–nanocone arrays as high performance non-noble metal electrocatalysts for hydrogen generation

Abstract

The electrochemical hydrogen production from water splitting is a promising strategy for obtaining new energy sources and replacing fossil fuels. In this study, nickel nanocones were first deposited on a nickel foam substrate using a direct current method. Then, a nickel–cobalt–manganese ternary alloy with a nanosheet morphology was deposited on the nanocones using a cyclic voltammetry method with different cycles and sweep rates. The results show that the sample synthesized in 3 cycles with a sweep rate of 10 mV s⁻¹ exhibits the best electrocatalytic activity and requires −81, −121, and −214 mV overpotentials to reach 10, 20 and 100 mA cm⁻² current densities, respectively. Electrochemical impedance spectroscopy studies also improved the HER performance with the lowest charge transfer resistance among all of the synthesized electrodes. This study introduces an effective and facile method for the fabrication of highly active and stable electrocatalysts.