High Performance Core/Shell Ni/Ni(OH) ₂ Electrospun Nanofiber Anodes for Decoupled Water Splitting

Abstract Decoupled water splitting is a promising new path for renewable hydrogen production, offering many potential advantages such as stable operation under partial‐load conditions, high‐pressure hydrogen production, overall system robustness, and higher safety levels. Here, the performance of electrospun core/shell nickel/nickel hydroxide anodes is demonstrated in an electrochemical‐thermally activated chemical decoupled water splitting process. The high surface area of the hierarchical porous electrode structure improves the utilization efficiency, charge capacity, and current density of the redox anode while maintaining high process efficiency. The anodes reach average current densities as high as 113 mA cm ⁻² at a working potential of 1.48 V _RHE and 64 mA cm ⁻² at 1.43 V _RHE , with a Faradaic efficiency of nearly 100% and no H ₂ /O ₂ intermixing in a membrane‐free cell.