Super-aerophobic B-doped coral-like hierarchical nanoarray electrode for overall water splitting

The rational design of highly active, non-precious electrocatalysts for overall water splitting is crucial for large-scale hydrogen production. Herein, a coral-like B-doping hierarchical nanoarray(B–FeCoNi-LDH@NF) with two-dimensional metal boride nanoflakes growing on FeCoNi LDH nanowires are constructed by boronation induced surface reconfiguration strategy. The introduction of B-doping generates abundant oxygen vacancies and crystalline-amorphous phase interfaces, creating a three-dimensional hierarchical nanoarray structure with superaerophobic properties. The optimized B₁₀–FeCoNi-LDH@NF electrode exhibits exceptional electrocatalytic performance, achieving low overpotentials for hydrogen evolution (56 mV at 10 mA cm⁻²) and oxygen evolution (169 mV at 10 mA cm⁻²). An alkali-water electrolyzer using B₁₀–FeCoNi-LDH as both cathode and anode delivers a low voltage of 1.54 V at 10 mA cm⁻². DFT calculations show B-doping modulates Fe, Co, and Ni active sites, lowering the energy barrier for HER and OER rate-determining steps. This work provides a strategy for designing high-performance, non-precious multifunctional electrodes for water splitting.