State Key Laboratory of Pollution Control and Resource Reuse, Tongji University, Shanghai 200092, China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, China.
State Key Laboratory of Pollution Control and Resource Reuse, Tongji University, Shanghai 200092, China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, China.
Sci Total Environ. 2019 Feb 10;650(Pt 1):1112-1121. doi: 10.1016/j.scitotenv.2018.09.134. Epub 2018 Sep 11.
Pharmaceuticals have been frequently detected in various water bodies, posing potential threat to human health and ecological environment. In this work, ZnFe-LDH derived mixed metal oxides (ZnO/ZnFeO, ZnFeMMO) were innovatively adopted to modulate the g-CN photocatalytic performance for the enhanced degradation of ibuprofen (IBF) and sulfadiazine (SDZ) as targeted pollutants. Characterization analyses indicated that the g-CN/ZnFeMMO composites were in the feature of rationally-designed microarchitecture, increased specific surface area, improved light absorbance and efficient charge separation, thereby resulting in promoted photocatalytic activities. Furthermore, the ratio of g-CN to ZnFeMMO in the composites was found to exert significant effects on the resulted microstructures and properties. The results showed that the composite with low g-CN content of 1.0 wt% or high g-CN content of 90 wt% exhibited the optimum catalytic activity for the degradation of IBF or SDZ, respectively. Such distinct structure-activities can be attributed to the different dominated reactive species in two cases: h for IBF degradation but OH for SDZ degradation. A Z-scheme mechanism was proposed for the charge separation, together with ZnFeO as a light sensitizer. Degradation pathways for IBF and SDZ were established by ESI-QToF-MS technology. This work provided a new perspective to develop rationally-architectured g-CN based photocatalysts for the decontamination of water polluted by pharmaceuticals.
药品已在各种水体中频繁检出，对人类健康和生态环境构成潜在威胁。在这项工作中，创新性地采用 ZnFe-LDH 衍生的混合金属氧化物（ZnO/ZnFeO、ZnFeMMO）来调节 g-CN 的光催化性能，以增强其对目标污染物布洛芬（IBF）和磺胺嘧啶（SDZ）的降解性能。表征分析表明，g-CN/ZnFeMMO 复合材料具有合理设计的微观结构、增加的比表面积、提高的光吸收和有效的电荷分离，从而促进了光催化活性。此外，复合材料中 g-CN 与 ZnFeMMO 的比例对所得微结构和性能有显著影响。结果表明，复合材料中 g-CN 含量为 1.0wt%或 90wt%时，对 IBF 或 SDZ 的降解表现出最佳催化活性。这种明显的结构-活性可以归因于两种情况下不同的主导活性物质：h 用于 IBF 降解，而 OH 用于 SDZ 降解。提出了一种 Z 型机制用于电荷分离，同时 ZnFeO 作为光敏剂。通过 ESI-QToF-MS 技术建立了 IBF 和 SDZ 的降解途径。这项工作为开发合理结构的基于 g-CN 的光催化剂用于净化受药品污染的水提供了新的视角。
