Co2(P4O12)/CoSe2 heterostructures grown on carbon nanofibers as an efficient electrocatalyst for water splitting†

The utilization of efficient and pollution-free water splitting hydrogen production technology is of great significance for alleviating environmental problems and achieving sustainable human development. The prospects of exploring highly efficient electrocatalytic activity, low-cost, and high-stability catalysts is vast, but there are still huge challenges. In this work, ZIF-67 derived Co₂(P₄O₁₂) and CoSe₂ heterostructures (Co₂(P₄O₁₂)/CoSe₂/CNFs) loaded on carbon nanofibers have been constructed using a combination of an in situ growth method and electrostatic spinning technique. The Co₂(P₄O₁₂)/CoSe₂/CNFs composite catalyst exhibited the highest oxygen evolution reaction (OER) activity (315 mV) and hydrogen evolution reaction (HER) activity (221 mV) at a current density of 10 mA cm⁻². After stability tests, the current density retention rates for the OER and HER are 96.1% and 85.6%, respectively. The combination of Co₂(P₄O₁₂)/CoSe₂/CNFs-2 was employed in a water electrolysis system, resulting in the attainment of a current density of 10 mA cm⁻² at a cell voltage of only 1.71 V. This paper provides a new idea for exploring bifunctional catalysts for water electrolysis, which has good prospects for development.