Co(PO)/CoSe 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 Co 2 (P 4 O 12 ) and CoSe 2 heterostructures (Co 2 (P 4 O 12 )/CoSe 2 /CNFs) loaded on carbon nanofibers have been constructed using a combination of an in situ growth method and electrostatic spinning technique. The Co 2 (P 4 O 12 )/CoSe 2 /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 Co 2 (P 4 O 12 )/CoSe 2 /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. The construction of heterojunctions can regulate the local electronic structure of metal sites and promote mass transfer. ZIF-67 exposes more active sites. The combination of CoSe 2 , Co 2 (P 4 O 12 ) and CNFs improves the conductivity of the material.