Interface Engineering of Flower-like Co₂P/WO_3-x/Carbon Cloth Catalysts with Oxygen Vacancies for Efficient Oxygen...

The Constructing an efficient and low-cost oxygen evolution reaction (OER) electrocatalyst is critical for improving the performance of electrolysis in alkaline water. In this study, a self-supported electrocatalyst of flower-like cobalt phosphide and tungsten oxide (Co₂P/WO_3-x/CC) was prepared on carbon cloth (CC) surface by hydrothermal reaction with solution immersion etching and phosphorization annealing under H₂/Ar atmosphere. This strategy can generate oxygen vacancies (O_V), improving the speed of charge transfer between cobalt phosphide (Co₂P) and tungsten oxide (WO_3-x) components. The catalyst greatly increases the electrochemical active surface area, which is beneficial for efficient oxygen evolution. Electrochemical testing studies show that in 1.0 M KOH solution, Co₂P-WO_3-x/CC catalyst exhibits good OER activity, with a low overpotential of 254 mV at 10 mA cm^-2, a small Tafel slope of 58.32 mV dec^-1. The synergistic effect of oxygen vacancies and Co₂P with WO_3-x can regulate electronic structures, expose more active sites, and cooperatively enhancing the OER activity. This study provides a workable strategy for preparing efficient non-noble metal OER electrocatalysts on engineered interfaces and O_V.