Preparation of dendritic CuNi@CF catalysts by one-step electrodeposition: Achieve efficient hydrogen evolution reaction from seawater

Seawater electrolysis can address the freshwater crisis and promote sustainable development, but there are several challenges, such as low catalyst activity and susceptibility to corrosion. We synthesized self-supported CuNi@CF catalysts on copper foam surfaces using a one-step electrodeposition method. In simulated seawater (6 M KOH+0.5 M NaCl), CuNi@CF showed excellent performance in the hydrogen evolution reaction with a low overpotential of 14 mV at 100 mA cm- 2, outperforming Pt/C@CF (148 mV) and most reported catalysts. The enhanced catalytic activity is attributed to the introduction of copper, which enhances electron transfer and forms a dendritic morphology with high surface area and active sites. We optimized the Ni/Cu ratio to determine the optimal experimental conditions. Corrosion tests validated the durability of CuNi@CF, showing a tiny potential drop after 100 h. The dendritic structure and Raman spectroscopy analysis supported the stability of the catalyst. The CuNi@CF||NiFe LDH electrolyzer also demonstrated excellent water decomposition efficiency in simulated seawater at 80 degrees C. This study thus presents promising prospects for hydrogen production via seawater electrolysis.