Bifunctional electrocatalysts based on nano-fan-shaped NiCoP for hydrogen evolution and urea oxidation reactions

Replacing the conventional oxygen evolution reaction (OER) with the urea oxidation reaction (UOR) coupled with hydrogen evolution reaction (HER) represents a highly promising strategy for low-energy hydrogen production. In this study, we developed a novel nanosheet-assembled fan-shaped NiCoP electrocatalyst via a two-step hydrothermal-phosphidation method. Benefiting from its unique electronic structure and abundant active sites, the NiCoP catalyst requires only 1.12 V (vs. RHE) for UOR and an overpotential of 70 mV for HER to reach a current density of 10 mA·cm −2 . Remarkably, no obvious degradation in activity was observed even after 50 h of continuous operation. Moreover, when employed in a urea-assisted electrolyzer (HER||UOR), the catalyst achieves 10 mA·cm −2 at a cell voltage of merely 1.37 V. This work provides new insights into the development of low-cost and energy-efficient urea electrolysis for hydrogen production.