Multiple p-d hybridizations in Fe2P–CoFe2O4 heteronanosheets boost the electrocatalytic performance for alkaline water splitting

The realization of alkaline water splitting depends on the economically feasible electrocatalyst with high stability associated with performance toward hydrogen/oxygen evolution reaction. In this work, we introduce Fe2P to CoFe2O4 nanosheets via in-situ phosphorization leading to the rich heterointerfaces results in multiple p-d hybridizations contributing to a boosted OER performance with overpotential at 100 mA cm−2 decreased from 309 mV (CoFe2O4) to 275 mV (Fe2P–CoFe2O4); moreover, OER stability is simultaneously promoted. Additionally, the HER performance is also significantly enhanced with only 118 mV and 204 mV to attain 10 mA cm−2 and 200 mA cm−2, superior to CoFe2O4 requiring 154 mV and 318 mV, respectively. The robust HER performance originates from the presence of Fe2P and CoFe2O4 possessing balanced hydrogen binding strength and robust water dissociation capability. Water splitting performance of Fe2P–CoFe2O4 is also superior to Pt/C–IrO2.