A molybdenum-promoted nickel–aluminum alloy catalyst for high-efficient hydrogenation reduction of nitrate to ammonia and nitrogen

Nitrate pollution in water necessitates efficient catalytic solutions for its conversion into harmless or valuable products. In this work, a molybdenum-promoted nickel–aluminum alloy (NAMCat) catalyst via alkaline leaching for the hydrogenation reduction of nitrate to N 2 and NH 3 was developed. The catalyst achieves over 99% nitrate conversion with brilliant product selectivity of N 2 /NH 3 under mild conditions. The characterization results revealed that Mo doping critically induces a sponge-like porous architecture and fosters synergistic Ni–Mo active sites, which collectively enhance mass transport, hydrogen activation and reaction kinetics. The catalyst also demonstrates remarkable stability, recyclability, and tolerance to common interfering ions. A reaction mechanism based on the porous and electronic structure of NAMCat was also proposed. This work provides a cost-effective, non-noble-metal catalyst strategy for simultaneous nitrate remediation and nitrogen resource recovery. A molybdenum-promoted Ni–Al alloy catalyst was developed for highly-efficient nitrate hydrogenation to N 2 /NH 3 . It achieved >99% conversion with remarkable stability, recyclability, and tolerance to common interfering ions.