State Key Laboratory of Urban Water Resources and Environment (SKLUWRE), School of Environment, Harbin Institute of Technology, Harbin, 150090, China.
Xiongan Planning & Design Institute, Xiongan, 071000, China.
Chemosphere. 2020 Aug;252:126577. doi: 10.1016/j.chemosphere.2020.126577. Epub 2020 Mar 23.
To clarify the photocatalytic mechanisms of metal-doped BiWO for fluoroquinolones (FQs) degradation, the effects of the chemical characteristics of four metals, molar ratios of the doped metals, morphology of the catalysts, and electrostatic interactions on the degradation of norfloxacin (NOR) and ciprofloxacin (CIP) were evaluated under visible light irradiation. Experimental results implied that the doping of Mg, Fe, Zn and Cu dramatically improved the photodegradation of BiWO for NOR and CIP removal, in which 1% Mg/BiWO exhibited the highest degradation rate of 89.44% for NOR and 99.11% for CIP. Photodegradation of NOR fitted to the pseudo-first-order model (k value of 0.02576 min), whereas that of CIP be better described by pseudo-second-order model. Moreover, the two FQs photodegradation pathways and the possible intermediates were summarized. The mechanisms of the metal dopants for the enhancement of photocatalytic activity were attributed to its enhanced specific surface area, electrostatic absorption, as well as the significant photogeneration of ·O and h. Also, the photocatalyst exhibited a high stability with 78.5% photocatalytic performance after four cycles of repeated usage.
为了阐明金属掺杂 BiWO 光催化降解氟喹诺酮类（FQs）的机制，研究了四种金属的化学特性、掺杂金属的摩尔比、催化剂的形态以及静电相互作用对可见光照射下诺氟沙星（NOR）和环丙沙星（CIP）降解的影响。实验结果表明，Mg、Fe、Zn 和 Cu 的掺杂显著提高了 BiWO 对 NOR 和 CIP 去除的光降解性能，其中 1%Mg/BiWO 对 NOR 和 CIP 的最高降解率分别为 89.44%和 99.11%。NOR 的光降解符合准一级动力学模型（k 值为 0.02576 min），而 CIP 的光降解则更符合准二级动力学模型。此外，总结了两种 FQs 光降解途径和可能的中间产物。金属掺杂剂增强光催化活性的机制归因于其增强的比表面积、静电吸附以及·O 和 h 的显著光生成。此外，该光催化剂在重复使用四次后仍保持 78.5%的光催化性能，具有较高的稳定性。
