Sun Shiquan, Tang Qingxin, Yu Taiping, Gao Yang, Zhang Wei, Zhou Lean, Elhegazy Hosam, He Kai
School of Hydraulic and Environmental Engineering, Changsha University of Science & Technology, Changsha 410114, China; Key Laboratory of Dongting Lake Aquatic Eco-Environmental Control and Restoration of Hunan Province, Changsha 410114, China.
School of Hydraulic and Environmental Engineering, Changsha University of Science & Technology, Changsha 410114, China; Key Laboratory of Dongting Lake Aquatic Eco-Environmental Control and Restoration of Hunan Province, Changsha 410114, China.
Environ Res. 2022 Dec;215(Pt 1):114216. doi: 10.1016/j.envres.2022.114216. Epub 2022 Aug 31.
In this work, a floating photocatalyst was constructed by loading g-CN@BiMoO@AgI (GBA) nanocomposite on a modified polyurethane sponge via a simple dip-coating method and applied for the inactivation of Microcystis aeruginosa under visible light. GBA ternary photocatalyst was fabricated successfully and the morphology, structure, chemical state, and optical properties were characterized systematically. The floating catalyst achieved near 100% removal efficiency of algae cells under 6 h visible light irradiation and also could be retrieved and used at least three times repeatedly. The influences of various conditions on photocatalytic performance such as loading content of nanoparticles, algae density, and concentration of natural organic matters were also studied, which revealed that the GBA floating catalyst exhibited excellent photocatalytic performance of algae removal under different conditions. Furthermore, the physiological characteristics of algae cells during the photocatalytic process, including cell morphology, membrane permeability, Zeta potential, photosynthetic system, antioxidant system, and the metabolic activity were investigated. Results confirmed that the algae cells were severely damaged during the photocatalytic inactivation and the normal physiological functions were significantly affected, which resulted in the death of algae cells at last. Finally, a possible photocatalytic inactivation mechanism of algae cells was proposed. In summary, GBA floating catalyst can effectively inactivate Microcystis aeruginosa under visible light, which confirmed the high efficiency of the novel photocatalytic algae removal technology. Meanwhile, the recyclable floating material also makes the practical application in eutrophic waters of the algae removal technology possible.
在本工作中，通过简单的浸涂法将g-CN@BiMoO@AgI（GBA）纳米复合材料负载在改性聚氨酯海绵上构建了一种漂浮光催化剂，并将其应用于可见光下铜绿微囊藻的灭活。成功制备了GBA三元光催化剂，并对其形貌、结构、化学状态和光学性质进行了系统表征。该漂浮催化剂在可见光照射6小时下实现了近100%的藻细胞去除效率，并且可以回收并至少重复使用三次。还研究了各种条件对光催化性能的影响，如纳米颗粒负载量、藻密度和天然有机物浓度等，结果表明GBA漂浮催化剂在不同条件下均表现出优异的光催化除藻性能。此外，还研究了光催化过程中藻细胞的生理特性，包括细胞形态、膜通透性、Zeta电位、光合系统、抗氧化系统和代谢活性。结果证实，藻细胞在光催化灭活过程中受到严重损伤，正常生理功能受到显著影响，最终导致藻细胞死亡。最后，提出了藻细胞可能的光催化灭活机制。综上所述，GBA漂浮催化剂在可见光下能有效灭活铜绿微囊藻，证实了新型光催化除藻技术的高效性。同时，这种可回收的漂浮材料也使得该除藻技术在富营养化水体中的实际应用成为可能。
