Facile Nitridation of a MoNi Alloy with an Optimized Electronic Structure toward Boosted Overall Hydrazine Splitting Assisted by Solar Light

Hydrazine oxidation reaction (HzOR)-assisted hydrogen production enables energy efficiency and performance improvement by avoiding a sluggish oxygen evolution reaction, yet its catalyst development is hindered by complex synthesis and limited external field integration. Herein, we report a cost-effective and scalable approach to construct nitride electrodes directly from a commercial MoNi alloy foam via one-step ammonia nitridation. The optimized catalysts exhibited a tailored electronic structure derived from d-electron complementation between Ni and Mo, promoting hydrazine dehydrogenation kinetics and hydrogen adsorption. Under rational design, the potentials could reach as low as -0.24 V for the HER and 0.046 V for the HzOR at a high current density exceeding 600 mA cm⁻² in an alkaline electrolyte, which is comparable to the state-of-the-art materials in references. Furthermore, full-cell operation demonstrated cell voltages as low as 0.01 and 0.109 V at 10 and 100 mA cm⁻², respectively. Thanks to solar light assistance, there was an 87.4% energy consumption reduction for the HER at 10 mA cm⁻² and a 78.1% reduction for the HzOR at 50 mA cm⁻². We provided a viable route in this work to engineer alloy-derived nitride electrocatalysts integrated with light-field enhancement for energy-saving hydrogen production.