Wafer-Scaled III-Nitrides Nanowire Photocathodes Enabled by Synergistic Dual-Electron Extraction for Efficient Solar-to-Hydrogen Conversion

at 0 V vs. RHE-representing a 37.8-fold enhancement over the pristine device-with an onset potential of 0.82 V vs. RHE, while sustaining stable hydrogen generation for over 300 h without additional protective layers. Specifically, an electron-blocking layer was incorporated within p‑InGaN nanowires to suppress electron backflow toward the substrate and promote transport to the nanowire/electrolyte interface. Furthermore, surface anion doping in InGaN nanowires significantly enhances the band bending of InGaN, which promotes interfacial electron transfer while simultaneously optimizing hydrogen adsorption energy, thereby accelerating the hydrogen evolution reaction rate. The proposed synergistic dual-electron extraction strategy markedly improves the electron utilization efficiency of single-junction InGaN nanowires, providing a novel pathway to address the intrinsic limitations of wafer-scale III-V nitride photoelectrodes.