Joule heating-assisted preparation of high-efficiency, long-term stability FeNiMoO hydrogen evolution reaction catalyst

Abstract

Bulk NiFe alloy has attracted considerable attention in water-splitting to produce green hydrogen due to its low price and ability to be produced in large quantities and in large sizes. However, the catalytic activity of the bulk NiFe alloy could not meet the industrial demand. Hence, it is necessary to improve its catalytic activity.In this study, we report a simple immersion in ammonium molybdate solution followed by a fast Joule heating method to modify the surface with the formation of NiFeMo-O on NiFe foam, which shows excellent hydrogen evolution reaction (HER) performance.After 1.5h immersion and Joule heating treatment, the NiFe-Mo 1.5h -HTS only requires overpotentials of 368, 899, and 1220 mV to achieve current densities of 100, 600, and 1000 mA cm⁻², respectively. Moreover, it displays outstanding long-term stability for over 3000h at a current density of 400 mA cm⁻². The in-situ Raman spectroscopy tests confirmed that the metal oxides/(oxy)hydroxides play a key role in improving HER catalytic performance. This study provides valuable insights for enhancing the HER performance of bulk alloys and promotes their industrial application for green hydrogen production.