Key Laboratory of Wetland Ecology and Environment, Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun 130102, China; University of Chinese Academy of Sciences, Beijing 100049, China.
Department of Physical and Environmental Sciences, University of Toronto Scarborough, Toronto M1C 1A4, Canada.
Sci Total Environ. 2019 May 10;664:230-239. doi: 10.1016/j.scitotenv.2019.02.027. Epub 2019 Feb 2.
A ternary visible-light driven photocatalyst, Ag/BiVO/reduced graphene oxide (rGO) composite was manufactured by hydrothermal strategy. The optimized products were characterized by XRD, SEM, HRTEM, EDS, XPS, DRS, Raman spectra, PL, BET, photocurrent density and EIS analysis. Compared to pure BiVO, the fabricated ternary composite showed enhanced photocatalytic ability to decompose pollutant under visible light. Triclosan was completely removed after 100 min in solution with 1 mg/mL photocatalyst under visible light irradiation. Repeated cycle tests demonstrated the photo-stability and reusability of composite to decompose triclosan, indicating that this material could be utilized repeatedly. The upgraded photocatalytic ability was attributed to the addition of Ag and rGO, which enhanced the charge separation and inhibited the recombination of photogenerated electrons and holes. The EPR spin-trap technique (with DMPO) was performed to identify the radicals produced in Ag/BiVO/rGO under the visible light, and trapping experiments were conducted to determine the main active species in the photocatalytic process of decomposing triclosan. Finally, seven reaction intermediates of triclosan were detected by LC-MS/MS and possible degradation routes were proposed.
采用水热法制备了一种三元可见光驱动光催化剂 Ag/BiVO/rGO 复合材料。通过 XRD、SEM、HRTEM、EDS、XPS、DRS、Raman 光谱、PL、BET、光电流密度和 EIS 分析对优化后的产物进行了表征。与纯 BiVO 相比，所制备的三元复合材料在可见光照射下具有更强的分解污染物的光催化能力。在 1mg/mL 光催化剂存在下，100min 后，溶液中的三氯生完全被去除。重复循环测试表明，复合材料具有光稳定性和可重复使用性，可用于重复分解三氯生。光催化能力的提高归因于 Ag 和 rGO 的加入，它们增强了电荷分离并抑制了光生电子和空穴的复合。通过 EPR 自旋捕获技术（使用 DMPO）来识别 Ag/BiVO/rGO 在可见光下产生的自由基，并进行捕获实验来确定在光催化分解三氯生过程中的主要活性物质。最后，通过 LC-MS/MS 检测到三氯生的 7 种反应中间体，并提出了可能的降解途径。
