Synergy of interfacial Zn–O–B bond and surface oxygen vacancy in BNNS/GaZnON for efficient photocatalytic overall water splitting

Abstract Both surface oxygen vacancies and interfacial chemical bonds in heterojunction engineering are regarded as promising approaches to efficient photo‐carrier utilization, yet the possible synergy underneath is still ambiguous in photocatalytic overall water splitting. Herein, boron nitride nanosheets (BNNS) were adhered to the GaZnON surface via a facile one‐pot nitridation process, achieving a 3.2 times enhancement in overall water splitting. The excellent photocatalytic performance could be ascribed to the greatly reduced detrimental carrier recombination by the strengthened synergistic interaction by the interfacial Zn–O–B bond and surface oxygen vacancies in GaZnON, in which the transfer of photogenerated electrons from the electronic localization region induced by oxygen vacancies in GaZnON to BNNS along the specific electron transfer channel of the interfacial Zn–O–B bond is facilitated. Moreover, surface oxygen vacancies that adsorbed water and accelerated water dissociation to activate H–OH optimized the reaction pathway. This work thoroughly elaborates on the synergetic effect of interfacial chemical bonds and surface oxygen vacancies in BNNS/GaZnON heterojunction, highlighting the importance of modulating carrier dynamics in photocatalytic overall water splitting.