NiCoP–CeO2 composites for efficient electrochemical oxygen evolution

Abstract

In this study, a novel NiCoP–CeO₂ composite was constructed on a Ni foam by a simple hydrothermal method and thermal phosphating strategy. In the OER test, NiCoP–CeO₂ exhibited a low overpotential of 217 mV at 10 mA cm⁻², 45 mV dec⁻¹ of Tafel slopes. With the help of theoretical calculations and experimental characterization, the reason for performance improvement was analyzed in depth. The results show that CeO₂ leads to a confinement effect, maintaining the nanosheet morphology of NiCo-LDHs, which contributes to sustaining the catalyst in favourable contact with H₂O and minimizing the OER potential. Furthermore, by loading CeO₂ onto NiCoP, the hydrophilicity of the catalyst is significantly enhanced. Our work provides an ingenious synthesis strategy for the preparation of efficient and inexpensive electrocatalytic materials.