Dual‐Plane Engineered GO‐Shielded GaN Core–Shell Nanowires for Cl − ‐Resilient and Durable Seawater Splitting Photoelectrodes

ABSTRACT Vertical gallium nitride (GaN) nanowire core and few‐layer graphene oxide shell (GO/GaN CS NWs) represent a novel core‐shell structure with unique double‐bond phenomena, enabling dual energy band mechanisms that enhance direct seawater‐splitting efficiency. At the GO/GaN interface, atomic interactions form configurations such as C–O–N–Ga (N‐polar van der Waals interactions) and C–O–Ga–N (Ga‐polar covalent interactions), which facilitate efficient photon absorption and charge migration into the graphene oxide shell. These mechanisms promote effective electron–hole separation and rapid interfacial charge transfer, crucial for photocatalytic processes. Two energy band probability mechanisms, both type‐II (Ga‐polar) and Z‐scheme (N‐polar), are expected to play a key role in enhancing photocatalytic processes, aiding in the oxidation of seawater through the combined effects of thermal energy and photon absorption. Blockage of active sites and corrosion induced by chloride ions are common issues in direct seawater splitting, constituting a significant challenge in this process. We suggest that N‐polar GaN and the hydroxide ions in GO act as promising photoanode electrodes by repelling chloride ions during direct seawater splitting. The study highlights the significance of core–shell architectures, specific chemical bonds, double‐bond phenomena, dual energy bands, theoretical analysis, temperature‐dependent OER conditions, photocatalytic activity, and chloride‐ion repelling ability in advancing sustainable energy technologies.