Ultrafast combustion synthesis of nickel-based self-supporting electrocatalysts for high current density oxygen evolution reaction

Abstract

Developing cost-effective, high-performance electrocatalysts for the oxygen evolution reaction (OER) is essential for sustainable hydrogen production. Herein, we report an extremely simple and ultrafast combustion method to fabricate a self-supported OER electrocatalyst (NF–NiFe–OH). The synthesis involves immersing nickel foam in an ethanol/water solution containing iron nitrate, followed by direct ignition in air. The entire combustion process is completed within a few seconds, thereby forming an active electrochemical layer composed of iron oxide and nickel hydroxide, and this active layer is firmly attached to the three-dimensional nickel foam. The optimal NF–NiFe–OH catalyst delivers outstanding OER performance in 1.0 M KOH, achieving current densities of 100, 500, and 1000 mA cm⁻² at overpotentials of only 305, 559, and 841 mV, respectively. It exhibits a small Tafel slope of 84.7 mV dec⁻¹, a low charge-transfer resistance of 8.65 Ω, and a high electrochemical active surface area. Moreover, the catalyst demonstrates excellent long-term stability, sustaining 800 mA cm⁻² for 145 h with negligible degradation. This work provides a rapid, scalable, and energy-efficient strategy for synthesizing high-performance non-precious OER electrocatalysts, highlighting the potential of combustion chemistry in advancing water electrolysis technology.