Co2P2O7@MoO3/NF composite electrocatalysts by different phosphorus sources for efficient oxygen evolution reaction and overall water splitting

Abstract

Electrocatalysts comprising MoO₃ coated by Co₂P₂O₇ nanocrystals were grown on a nickel foam (NF) substrate. The applicability of the nanocomposite material (Co₂P₂O₇@MoO₃/NF) as an electrode for the oxygen evolution reaction (OER) and overall water splitting was verified. The as-synthesized product showed the overpotentials of 227 and 377 mV to drive the OER at current densities of 50 and 100 mA cm⁻², respectively. Furthermore, the voltage of Co₂P₂O₇@MoO₃/NF as a bifunctional overall water splitting catalyst was 1.55 V at 10 mA cm⁻². Co₂P₂O₇@MoO₃/NF@NF (+)//Co₂P₂O₇@MoO₃/NF (−) can maintain >80% of its initial current density after 30 h at 15 mA cm⁻². The Co₂P₂O₇@MoO₃/NF electrode also showed a low hydrogen evolution reaction overpotential of 58.7 mV at 10 mA cm⁻². The excellent oxygen evolution and electrochemical water decomposition stability of the catalyst have broad application prospects.