Synergistically coupled CoMo/Fe2O3 electrocatalyst for highly efficient and stable overall water splitting

Constructing bifunctional non-precious metal electrocatalysts with advanced industrial value and excellent electrocatalytic performance to achieve efficient overall water splitting is important but difficult. Herein, a heterogeneous electrocatalyst comprising of CoMo alloys anchored Fe 2 O 3 nanosheets was prepared by hydrothermal and electrodeposition methods. The strongly coupled interfaces between the CoMo alloys and Fe 2 O 3 nanosheets promote charge redistribution, which could improve electron transfer efficiency and accelerate reaction kinetics, potentially optimizing reactant adsorption energy. Further density functional theory (DFT) calculations reveal that the construction of CoMo/Fe 2 O 3 /NF heterostructured catalyst facilitates to promote interfacial charge redistribution and enhance charge transfer capacity, thus boosting the catalytic performance. Benefiting from this, the optimal CoMo/Fe 2 O 3 /NF heterostructure demonstrates a minimal overpotential of 71 mV at 10 mA cm −2 for the HER and 266 mV at 50 mA cm −2 for the OER. Remarkably, the catalyst served as a bifunctional electrode for water splitting, resulting in a cell voltage down to 1.5 V at a current density of 10 mA cm −2 . This research provides an effective way for the construction of non-precious iron oxides-based bifunctional electrocatalysts using alloy/metal oxide interfacial engineering strategy.