Highly dispersed nickel nitride nanoparticles on nickel nanosheets as an active catalyst for hydrazine electrooxidation

Synthesis of high-performance and low-cost anode electrocatalysts is a central issue in the development of direct hydrazine fuel cells as a viable energy conversion technology. Herein, we report a careful study of nickel nitride as a promising catalyst towards electrooxidation of hydrazine. A hierarchically nanostructured catalyst consisting of tiny Ni3N nanoparticles dispersed on Ni nanosheets is synthesized using a hydrothermal method followed by nitridation treatment. The thus-prepared catalyst exhibits an impressively high activity, good durability and a nearly 100% selectivity towards hydrazine electrooxidation following the 4-electron-pathway, which compares favorably with most DHFC anode catalysts reported to date. Density functional theory calculations were conducted to further understand the outstanding performance of nickel nitride towards hydrazine electrooxidation.