State Key Laboratory of Materials Processing and Die & Mould Technology, School of Materials Science and Engineering, Huazhong University of Science and Technology, Wuhan 430074, Hubei, China.
State Key Laboratory of Materials Processing and Die & Mould Technology, School of Materials Science and Engineering, Huazhong University of Science and Technology, Wuhan 430074, Hubei, China.
J Colloid Interface Sci. 2022 Oct 15;624:137-149. doi: 10.1016/j.jcis.2022.05.134. Epub 2022 May 27.
In this study, zincperoxide (ZnO) with broad energy gap was firstly used for visible-light-induced photocatalytic degradation of tetracycline (TC) and inactivation of Escherichia coli (E. coli). A small amount of ZnO (10 mg) could efficiently degrade 100 mL of 50 mg/L TC in a wide pH range (4-12), and the degradation performance was rarely suppressed by common matrix species and natural water sources. Also, 100 mg/L ZnO could inactivate around 7-log E. coli cells within 60 min under visible-light irradiation. Quenching experiments and electron paramagnetic resonance (EPR) results confirmed that superoxide radical (•O) and singlet oxygen (O) were the main reactive oxygen species (ROS), which were attributed to the self-sensitization of TC and the photoexcitation of released HO under the catalysis of Zn(OH) from the hydrolysis of partial ZnO, respectively. The pathways of TC degradation and processes of visible-light-induced TC degradation and E. coli inactivation were proposed and deduced in detail. This work presented the enhanced visible-light photocatalytic activities of ZnO for antibiotic degradation and bacterial inactivation, and provided a deep insight into the mechanisms of visible-light-induced TC degradation andE. coli inactivation over ZnO.
在这项研究中，首次使用具有宽能隙的氧化锌 (ZnO) 进行可见光诱导的四环素 (TC) 光催化降解和大肠杆菌 (E. coli) 的失活。少量的 ZnO（10 mg）可以在很宽的 pH 值范围（4-12）内有效降解 100 mL 的 50 mg/L TC，且降解性能很少受到常见基质种类和天然水源的抑制。此外，在可见光照射下，100 mg/L ZnO 可以在 60 分钟内使大约 7 对数的 E. coli 细胞失活。猝灭实验和电子顺磁共振 (EPR) 结果证实，超氧自由基 (•O) 和单线态氧 (O) 是主要的活性氧物种 (ROS)，这归因于 TC 的自敏化和部分 ZnO 水解释放的 HO 在 Zn(OH) 的催化下的光激发。详细提出并推导了 TC 降解途径以及可见光诱导 TC 降解和 E. coli 失活过程。这项工作展示了 ZnO 增强的可见光光催化活性，用于抗生素降解和细菌失活，并深入了解了 ZnO 上可见光诱导的 TC 降解和 E. coli 失活的机制。
