Self-Supported Fe-Doped MoNi₄ Alloy Nanosheet Array as a Trifunctional Electrocatalyst for Water and Urea Splitting

Abstract

Developing a high-performance and glorious non-noble-metal-active material to facilitate the catalytic reaction procedure is significant for electrochemical water and urea splitting. Here, an Fe-doped MoNi 4 alloy nanosheet array product vertically grown on Ni foam is obtained and used as the trifunctional electrocatalyst for hydrogen generation by water and urea decomposition. The MoNi 4 alloy nanosheet arrays with the incorporation of Fe can furnish a more active site and transmissive corridor, increase the active surface area, and enhance conductivity to ameliorate the electrocatalytic performance. Strikingly, the optimized MoNi 4 -Fe 0.5 exhibits outstanding trifunctional properties for hydrogen and oxygen evolution and urea oxygen reactions (HER, OER, and UOR), with low potentials of −0.050, 1.499, and 1.380 V to attain 10 mA cm –2, respectively. In addition, the constructed two-electrode electrolyzer applying MoNi 4 -Fe 0.5 as both the anode and cathode needs voltages of merely 1.54 and 1.40 V to actuate 10 mA cm –2 for water and urea electrolysis and also possesses good durability. This work proposes a beneficial instruction to exploit and build multifunctional, highly active, and economical electrocatalysts for verdantly renewable energy fields.