Novel Fe-Modulating Raney-Ni Electrodes toward High-Efficient and Durable AEM Water Electrolyzer

Anion exchange membrane (AEM) water electrolysis holds promise for green hydrogen production. One of the main challenges is the preparation of highly efficient electrodes with scalable techniques. Herein, a novel Fe-modulating Raney-Ni electrode (NFA-CA) is developed through atmospheric plasma spraying and chemical etching techniques. The resulting electrode demonstrates high bifunctional catalytic activities with low overpotentials and Tafel slopes (HER: 27 mV at 10 mA cm⁻², 20 mV dec⁻¹; OER: 169 mV at 10 mA cm⁻², 49 mV dec⁻¹), competing for precious-metal catalysts and leading transition-metal-based compounds reported in the literature. Moreover, the corresponding AEM electrolyzer only requires 1.56 V to drive 1 A cm⁻² and exceptional durability for 1000 h. Moreover, the AEM cell can reach 2 A cm⁻² at 1.79 V, exceeding the United States Department of Energy target for AWE systems (2 A cm⁻² at 1.80 V). The highly efficient and durable performance is attributed to the NiFe nanocrystals (core)-NiFe hydroxide (shell) nanostructures created by the treatment. This structure not only facilitates superior electrocatalytic properties but it is also maintained after 1000 h of continuous operation. It is consider that the present approach can offer an attractive route for scalable fabrication of NiFe-based electrodes for industrial AEM water electrolyzers.