Lattice distortion and electronic structure dual engineering of Bi4O5Br2 nanosheets for enhanced photocatalytic activity

Bi4O5Br2 has attracted considerable interest due to its unique photocatalytic properties. Nevertheless, its photocatalytic efficiency is significantly hindered by challenges such as low photogenerated carrier separation efficiency and insufficient adsorption capacity for target substances. In this study, for the first time, a simple doping strategy involving the incorporation of W into the lattice of Bi4O5Br2 was employed. This approach induced local lattice distortion and subsequently modulated the electronic structure, thereby markedly enhancing the photocatalytic property. Experimental results demonstrated that the 5 W photocatalyst exhibited exceptional antibacterial performance, achieving a complete (100 %) antibacterial rate against Pseudomonas aeruginosa within 10 min, and remarkable degradation efficacy, with a 97.0 % degradation rate of Rhodamine B in 40 min. Theoretical calculations further elucidated that the doped W induced a significant lattice distortion which had an important effect on modifying the electronic structure. W served as an enhanced active center to improve both the adsorption and activation capabilities of the photocatalyst surfaces. Additionally, it reduced the charge density overlap between the conduction band minimum (CBM) and valence band maximum (VBM), thereby significantly improving charge carrier separation efficiency. By systematically discussing the relationship between the regulation of crystal structure and electronic structure, this study provided new insights for the development of novel and efficient photocatalysts and showed the promising application prospects of such photocatalysts in environmental remediation.