Fe-doped NiCo2O4 hollow hierarchical sphere as an efficient electrocatalyst for oxygen evolution reaction

We prepared porous Fe-doped nickel cobaltate (Fe-NiCo2O4) hollow hierarchical nanospheres through a facile self-templated synthetic strategy. Due to the porous hollow structure and composition, the Fe-NiCo2O4 presented vastly superior electrocatalytic activity for the oxygen evolution reaction (OER), compared with NiCo2O4 and the majority of other OER catalysts. With an aim of stimulating a current density of 10 mA·cm−2, the Fe-NiCo2O4 catalyst needs an overpotential of 210 mV, which is on a par with the general properties of commercial IrO2. In addition, the Fe-NiCo2O4 catalyst performed stably in long-term testing. The excellent activity and long-term stability showed that such catalysts have great promise for widespread application in the field of water splitting.