Biosafe Bi2O2Se ultrathin nanosheet for water disinfection via solar-induced photothermal synergistic effect

作者：Mu, Xiaoyang; Li, Chao; Wang, Li; Zhang, Rumeng; Huang, Yingping^*; Yu, Xiang; Wong, Po Keung; Ye, Liqun^*

来源：Journal of Hazardous Materials, 2022, 440: 129808.

DOI：10.1016/j.jhazmat.2022.129808

• Bi2O2Se
• Biosecurity
• Photothermal synergy
• Sterilization
• Escherichia coli

Solar-induced sterilization via photothermal synergy has attracted enormous attention due to its zero-energy consumption and the elimination of hazardous chemical disinfectant. Herein, we successfully synthesized a super biosafety Bi2O2Se with crossed nanosheet structure (Bi2O2Se-CN) for the sterilization of Escherichia coli (E. coli) via solar-induced photothermal synergistic effect. In comparison to bulk Bi2O2Se, the lower light reflection and more efficient photogenerated charge carrier separation under visible-infrared light irradiation resulted in the excellent sterilization effect of Bi2O2Se-CN, with a sterilization efficiency of 99.9% under the synergistic effect of light and heat. The crossed ultrathin nanosheet structure and suitable band gap width of Bi2O2Se-CN are fundamental reasons for its enhanced light absorption and charge carrier separation efficiency. Mechanistic studies showed that Bi2O2Se-CN can completely inactivate bacteria via generating a large amount of reactive oxygen species (center dot O-2(-), center dot OH, and O-1(2)) to attack the cell membrane, which further resulted in the reduced activity of intracellular enzymes and the leakage of intracellular contents. The biosafety property of Bi2O2Se-CN was confirmed by in vivo toxicological evaluation on the mice model. This work provided new ideas for the design of more efficient, energy-saving, biocompatible and environmental friendly solar water purification projects.