Tuning interface density and electronic structure of NiS/Ni3S4 by Mo, Co co-doping for efficient urea electrooxidation reaction

Electrocatalysts exhibiting impressive catalytic capability and strong stability for urea oxidation reaction (UOR) are highly desired for direct urea fuel cells (DUFCs). Herein, a series of flower-like Mo, Co co-doped NiS/Ni3S4 heterostructure (Mo, Co-NSH) are controllable synthesized by a one-step hydrothermal method and utilized as catalysts for UOR. Taking advantages of massive heterojunctions, tunable electronic configuration and hierarchical flower-like topological structure together, the optimized component demonstrates advanced UOR performance compared to pure NiS/Ni3S4 and mono Co/Mo element doped NiS/Ni3S4, it delivers 147.1 mA cm(-2) at 1.6 V vs. RHE and works for more than 18 h without decay. The assembly direct urea hydrogen peroxide fuel cell (DUHPFC) with Mo-0.05, Co-NSH catalyst has an open-circuit voltage of 0.86 V and a maximum power density of 5.96 mW cm(-2) at 27 degrees C. The work provides a promising avenue for exploiting efficient electrocatalysts on both multi-metal doping and heterojunction engineering for electrochemical energy conversion and sewage treatment applications.