Highly Efficient and Self-supported Nanoporous Al-doped NiCu-S Electrode for Hydrogen Evolution Reaction

Abstract

In order to meet the demand for cheap, efficient, and stable catalysts in the field of water electrolysis for hydrogen production, ternary Al-Ni-Cu alloy ribbons with different atomic ratios were prepared in a vacuum induction apparatus by melt-spun rapid solidification technology. Then, Al-doped NiCu bimetallic sulfide catalysts were obtained by chemical dealloying treatment and hydrothermal sulfurization. The phase content and microstructure morphology were characterized by XRD and SEM. The results show that the electrode evolves from uniform nanosheets to tight nanoplates with the increase of Ni/Cu atomic ratios, which greatly increases the active specific surface area of the electrode. The electrochemical performance in 0.5 mol/L H2SO4 solution depicts that when the Ni/Cu atomic ratio is 2∶1, the self-supported S-np-Ni21Cu7 electrode only needs an overpotential of 245 mV to deliver the current density of 50 mA/cm2. Moreover, the S-np-Ni21Cu7 electrode manifests not only effective hydrogen evolution reaction kinetics but also superior stability and durability in long-term HER process.

Keywords

• dealloying
• nanoporous metal
• transition metal sulfide
• hydrogen evolution reaction