Ligand and Strain Synergistic Effect in NiFeP _0.32 LDH for Triggering Efficient Oxygen Evolution Reaction

Abstract

Abstract Developing efficient water‐splitting electrocatalysts to accelerate the slow oxygen evolution reaction (OER) kinetics is urgently desired for hydrogen production. Herein, ultralow phosphorus (P)‐doped NiFe LDH (NiFeP x LDH) with mild compressive strain is synthesized as an efficient OER electrocatalyst. Remarkably, NiFeP x LDH with the phosphorus mass ratio of 0.32 wt.% and compressive strain ratio of 2.53% (denoted as NiFeP 0.32 LDH) exhibits extraordinary OER activity with an overpotential as low as 210 mV, which is superior to that of commercial IrO 2 and other reported P‐based OER electrocatalysts. Both experimental performance and density function theory (DFT) calculation demonstrate that the doping of P atoms can generate covalent Fe─P coordination bonds and lattice distortion, thus resulting in the consequent depletion of electrons around the Fe active center and the downward shift of the d ‐band center, which can lead to a weaker adsorption ability of * O intermediate to improve the catalytic performance of NiFeP 0.32 LDH for OER. This work provides novel insights into the distinctive coordinated configuration of P in NiFeP x LDH, which can result in superior catalytic performance for OER.