Nickel-Coated Copper Foam Electrocatalytic Electrode for Energy-Saving Hydrogen Evolution and Value-Added Chemical Co-Generation.

Developing cost-effective, eco-friendly electrocatalysts with strong electrochemical performance is essential for advancing in water electrolysis. Noble metal-based catalysts offer excellent activity, but due to less availability and more expenses leads to an urgent demand for efficient, affordable, and earth-abundant alternatives. In this study, a bimetallic foam architecture (CuF@Ni) was fabricated by electrodeposition of Ni on CuF. This structure acts as both a conductive support and an active electrocatalyst. The synthesized CuF@Ni demonstrated superior HER activity and overpotential of 0.18 V at 50 mA/cm², while for MOR overpotential was observed 0.14 V at 50 mA/cm². CuF@Ni electrocatalytic electrode achieved a Faradaic efficiency ~100 %, with a formate (HCOO-) concentration of 7.9 mM during 150 C charge transfer. In a co-generation system integrating HER and MOR the onset potential was observed as lower 0.4 V and CuF@Ni required only 0.92 V to sustain the current density of 50 mA/cm², demonstrating significant energy savings. In addition, device consumes less power than theoretical water electrolysis under higher current density. Long-term stability tests confirmed minimal degradation under the harsh conditions. This study highlights CuF@Ni as a promising dual-functional electrocatalyst for efficient energy conversion for future renewable energy applications.