Heterostructured NiFe‐MOC/Ni ₃ Fe/Ni ₄ N for Photothermal‐Promoted Anion Exchange Membrane Water Electrolysis

ABSTRACT The oxygen evolution reaction (OER), characterized by sluggish kinetics, severely restricts the energy conversion efficiency in electrocatalytic water splitting for hydrogen production. Utilizing the photothermal effect to generate a localized thermal field presents a highly effective strategy for addressing this limitation. Herein, a novel OER electrocatalyst with photothermal function, the heterostructured metal–organic complex/alloy/nitride (NiFe‐MOC/Ni ₃ Fe/Ni ₄ N), was developed through a simple microwave assisted method. The introduction of Fe ³⁺ can establish a distinctive amorphous/crystalline heterostructure to regulate the catalyst's electronic configuration, optimize the adsorption characteristics of reaction intermediates, and significantly boost its photothermal effect. Under near‐infrared light irradiation, the NiFe‐MOC/Ni ₃ Fe/Ni ₄ N achieves 1000 mA cm ⁻² with a low overpotential of only 311 mV. Moreover, when utilized as an anode catalyst in an anion exchange membrane (AEM) electrolyzer integrated with the photothermal function, this electrocatalyst can enable the electrolyzer to attain approximately 57% energy savings in comparison with the conventional AEM electrolyzer. This work not only offers a highly efficient OER electrocatalyst but also provides fundamental understanding regarding the improvement of the energy conversion efficiency of electrocatalytic water splitting through the integration of the photothermal function.