Photocatalytic properties of bismuth-rich Bi4O5I2/BiOBr flowers prepared by one-step solvothermal method were studied

• Published in: Optical materials 2024-10, Vol.156, p.115958, Article 115958
• Main Authors: Wang, Junzhao, Wang, Limin, Chu, Chengzhi
• Format: Article
• Language: English
• Subjects: Bi4O5I2; BiOBr; Photocatalytic material; Solvothermal
• ISSN: 0925-3467
• DOI: 10.1016/j.optmat.2024.115958

In this paper, bismuth-rich three-dimensional Bi4O5I2/BiOBr hollow flower spheres were prepared by a one-pot solvothermal method. The anionic contaminant Rhodamine B (RhB) was used as the photocatalytic test contaminant. The results showed that the degradation rate of RhB was more than 99 %. Then Br element was introduced into Bi4O5I2 hollow flower balls, the diameter of flower balls decreased and flowers sparsely. With the increase of Br content, flower balls gradually increased in volume and became denser. Small and sparse flower balls increase the specific surface area of flower balls and increase the number of active sites, thus improving the REDOX capacity of photogenerated electrons and holes. Our findings suggest that both holes (h+) and superoxide radical anions (•O2−) are crucial players during photocatalysis. The aim of this study is to develop an efficient photocatalyst for the degradation of organic pollutants, and its photocatalytic mechanism is described theoretically. [Display omitted] •Innovative synthesis methodology: An efficacious one-pot solvothermal method yielded a bismuth-rich three-dimensional Bi4O5I2/BiOBr hollow flower bulb framework, enhancing the material's specific surface area and providing more reactive sites for photocatalysis.•Energy band structure optimization: Incorporation of Br element modifies the Bi4O5I2 energy band structure into a type II heterojunction, promoting efficient electron-hole separation and enhancing photocatalytic efficiency.•Proposed photocatalytic mechanism: A plausible photocatalytic mechanism was proposed, elucidating the pivotal role of h+ and .•O2− in the photocatalytic process, and constructing a theoretical model based on experimental findings.