Fig. 1. (a) Schematic diagram of charge transfer in CdS/BiOBr heterojunction under illumination. The illustration shows the SPV of CdS, BiOBr, CdS-CB, and BiOBr-CB. (b) The simple capacitor model composed of the tip-air-sample system. Reproduced with permission from Ref. [9]. Copyright 2025, Wiley.

Fig. 2. The schematic diagram of energy level for the individual samples in the dark (a) and under illumination (b). The schematic diagram of the charge transfer mechanism in CdS/BiOBr S-scheme heterojunction before (c) and after (d) illumination. Schematic diagram of charge transfer mechanism for the individual samples (e) and CdS/BiOBr S-scheme heterojunction with the surface state (f). Reproduced with permission from Ref. [9]. Copyright 2025, Wiley.