Prussian blue analogues derived Fe-NiCoP reveals the cooperation of Fe doping and phosphating for enhancing OER activity

The development of high-efficiency earth-rich and non-precious metal catalysts for oxygen evolution reactions is a critical and essential challenge. In this paper, Fe-doped NiCoP is prepared by phosphating iron-doped NiCo Prussian blue analogs (Fe-NiCo PBA) as a highly effective catalyst for electrocatalytic oxygen evolution reaction (OER). Fe-NiCoP exhibits superior OER performance with a low overpotential (266 mV at 10 mA cm−2) owing to the synergistic effect of Fe doping and phosphating. The Fe doping mainly decreases the energy barrier of the OH* dehydrogenation step, while phosphating significantly reduces the energy barrier of the OH adsorption step. This work reveals the mechanism of the synergistic effect of Fe doping and phosphating on catalysts and provides a new strategy for synthesizing metal-doped transition metal phosphides.