Copper–Iron Self-Supporting Electrode for Efficient Hydrogen Evolution Reaction

High-performance, cost-effective metal catalysts for alkaline hydrogen evolution reaction (HER) are crucial for advancing hydrogen energy applications. Iron, while affordable and conductive, suffers from excessive hydrogen adsorption due to its high d-band center, limiting its HER efficiency. This study presents a room-temperature synthesis of copper-iron self-supporting electrodes from iron microparticles, where the introduction of copper significantly improves water dissociation and hydrogen desorption. The electrode achieves low overpotentials of 153 and 431 mV at 10 and 300 mA cm^-2, respectively, with stable performance over 150 h. Notably, this simple method enables the direct post-treatment of iron at room temperature to produce self-supporting Cu-Fe composite electrodes, demonstrating strong potential for practical applications. Furthermore, the strategy of modulating iron's catalytic performance with copper not only optimizes catalytic efficiency but also offers valuable theoretical guidance for the design of other high-performance HER catalysts.