Porous Fe-Doped Ni₃P/CoP₃ Isomerism as High Durable Electrocatalyst for Generation of Hydrogen and Oxygen

The development of bifunctional catalysts enables the simultaneous operation of hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) in the same electrolyte. It is feasible to design high-performance catalysts by the addition of impurity atoms and the construction of composition. Herein, Fe-Ni₃P/Fe-CoP₃ nanostructures are obtained using metal–organic framework (MOF) as the precursor. It shows an overpotential of 71.7 mV (10 mA/cm²) for HER and 263.3 mV (50 mA/cm²) for OER under alkaline condition. Moreover, it also presents an OER overpotential of only 325.3 mV at the current densities of 1.5 A/cm². Using the catalyst as electrodes, the water electrolysis device provides a voltage of 1.566 V at 50 mA/cm². Density functional theory calculations reveal that the introduction of iron atoms and the presence of heterogeneous structures optimize the hydrogen adsorption energy.