Particle Engineering Laboratory, School of Chemical and Environmental Engineering, College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou City, Jiangsu, 215123, PR China.
Department of Chemistry and Laboratory of Advanced Materials, Fudan University, Shanghai, 200433, PR China.
Chemosphere. 2022 Nov;307(Pt 2):135967. doi: 10.1016/j.chemosphere.2022.135967. Epub 2022 Aug 8.
Controllable active site construction, crystal structure regulation and efficient charge separation are core issues in heterogeneous photo-Fenton. Herein, abundant oxygen vacancies and well-dispersed interfacial iron sites are simultaneously constructed in hierarchical nanosheet-assembled BiOCl microflowers. The composites exhibit superior performance in photo-Fenton oxidation of carbamazepine (10 mg L) with a low HO concentration (1.3 mM). The high performance highly depends on the synergistic effects between oxygen vacancies and iron species. Rather than modulating the valence band, the involvements of oxygen vacancies and iron species could modify the conduction band of BiOCl. The presence of oxygen vacancies promotes the migration of photo-generated electrons and accelerates the redox cycling of ≡Fe(III)/≡Fe(II) to boost the activation of HO to generate hydroxyl radicals, and oxygen vacancies can be well preserved after cyclic use. This work provides understanding on efficient utilization of oxygen vacancies and interfacial iron sites to assist photo-Fenton and the underlying electron transfer mechanism.
在多相光芬顿反应中，可控活性位构建、晶体结构调控和高效电荷分离是核心问题。在此，通过在分级纳米片组装的 BiOCl 微花中同时构建丰富的氧空位和分散良好的界面铁位，得到了复合材料。该复合材料在卡马西平（10mg/L）的光芬顿氧化反应中表现出优异的性能，HO 浓度（1.3mM）较低。这种高性能高度依赖于氧空位和铁物种之间的协同作用。氧空位和铁物种的参与并没有调节价带，而是可以修饰 BiOCl 的导带。氧空位的存在促进了光生电子的迁移，并加速了 ≡Fe(III)/≡Fe(II)的氧化还原循环，从而促进 HO 的激活以生成羟基自由基，并且氧空位在循环使用后可以很好地保留。这项工作提供了对有效利用氧空位和界面铁位以辅助光芬顿反应及其潜在电子转移机制的理解。
