Photoinduced metastable-charging d-orbital electrons of Re centers enhances interfacial charge migration behaviors for efficient coupling conversion

Directional and smooth transfer of charges across the interface is pivotal for heterojunction materials in terms of photochemical activity. However, large lattice mismatch and disordered interface inevitably exist in actual-prepared heterojunctions and bring great uncertainty in interfacial charge migration. Herein, an ingenious strategy with photoinduced metastable-charging d-orbital electrons of Re centers at the interface of ReS2/ZnIn2S4 (ReS2/ZIS) is clarified. This metastable interfacial electronic state is involved in creation of gradient charge migration channels. The charging process raises the occupancy of electron density, which provides large difference of electronic potential for the subsequent charge migration to ReS2. This gradient charge migration significantly accelerates the mobility and the electron injection rate at the interface, which achieves the 6.2-fold and 7.7-fold improvement. Consequently, the optimized 10% ReS2/ZIS composite exhibits the conversion rate for photocatalytic oxidation amine of 22.84 mmol·gcat−1 ·h−1, which is the highest efficiency achieved so far for photocatalytic amines oxidation coupling upon ReS2-based composites. This research furnishes original insights for charging orbital electrons to steer kinetics process of charge transfer and shed light on the design of advanced heterojunction materials for efficient solar energy conversion.