Modulating Ti t2g Orbital Bonding in Dual-Channeled TiO2/rGO Hybrid Architecture for Stable Photocatalytic Methanol to Hydrogen

Carbon materials are commonly integrated with TiO 2 to achieve high carrier mobility and excellent photocatalytic performance, and the chemical bond between TiO 2 − C is considered as a significant strategy to enhance efficiency. Nevertheless, few analyses have elucidated the formation mechanism of Ti 3 + − C bonds and the underlying reasons for the performance enhancement. To address these issues, this study conducts an in-depth investigation into the electronic structure of TiO 2 − C and demonstrates that the charge in the nonbonding molecular orbital t 2 g of Ti 3 + is transferred to the unoccupied 2 p energy level of C through the formation of 1π and 2π bonds, i.e., (Ti 3 d xz - C 2 p y ) and (Ti 3 d xy - C 2 p x ). The hybridization of t 2 g -2 p orbitals endows the Ti 3 + − C bond with higher carrier mobility and a stronger binding force, thereby contributing to stable photocatalytic H 2 production. Inspired by this scenario, the NSTiO 2 /rGO hybrid architecture, featuring the {101}/{001} surface heterojunction and the Ti 3 + − C interfacial chemical bond, has been constructed. As a result, the hybrid catalyst exhibited excellent photocatalytic cycling stability of 92.9 % $92.9 \,\%$ and an H 2 evolution rate of 33.4 mmolh −1 g −1 . This work proposes a strategy for designing efficient photocatalyst by regulating orbitals to achieve high-performance photocatalytic methanol splitting.