A chromium and nitrogen co-doped NiMo-based catalyst achieving high-efficiency and durable intermittent water electrolysis

Abstract

The integration of electrocatalytic water splitting with renewable energy is a green and sustainable approach to hydrogen production. However, hydrogen evolution reaction (HER) catalysts degrade rapidly under intermittent conditions, which poses a great challenge for their direct compatibility with renewable electricity. In this study, we reported a chromium (Cr) and nitrogen (N) co-doped NiMo catalyst that exhibits both efficient and stable HER performance under intermittent conditions. The introduction of Cr modulates the morphology of NiMo catalysts and stabilizes Mo to enhance HER intermittent stability. N-doping improves conductivity and electrochemically active surface area, boosting HER activity. Electrochemical in situ Raman spectroscopy shows that Cr reduces Mo dissolution during “start–stop” cycles, contributing to improved stability. This study offers valuable insights into the design of highly stable HER catalysts and the advancement of green hydrogen energy.