School of Chemistry, MOE Key Laboratory of Theoretical Chemistry of Environment, South China Normal University, Guangzhou, 510006, PR China.
Department of Environmental Engineering, Henan Polytechnic Institute, Nanyang, 473009, PR China.
Chemosphere. 2021 Oct;280:130770. doi: 10.1016/j.chemosphere.2021.130770. Epub 2021 May 5.
The development of efficient, effective, and large-scale treatment methods to address high-risk emerging contaminants (ECs) is a growing challenge in environmental remediation. Herein, a novel parallel coupling strategy of adsorption separation and photodegradation regeneration (parallel ASPR) is proposed; subsequently, an adsorptive photocatalyst (Zn-doped BiOI) is designed to demonstrate how to effectively eliminate fluoroquinolones (FQs) from water with the proposed ASPR scheme. Compared with pure BiOI, the addition of Zn during synthesis has a significant influence on the morphology and structure of the products, resulting in Zn-doped BiOI samples with up to 5 times the specific surface area, 32 times the adsorption capacity, and 20 times the photocurrent intensity. The optimized Zn-doped BiOI sample has an excellent adsorption efficiency for FQs with a removal rate that exceeds 95% after 5 min of adsorption for all 6 tested FQ antibiotics. Then the adsorbed contaminants can be effectively degraded during the later visible-light irradiation process, and the adsorbent can be regenerated synchronously, showing excellent ASPR cycling performances. The mechanisms of rapid adsorption and photocatalysis were explored via material characterizations, adsorption models, density functional theory calculations, and photogenerated species analyses. The results reveal that the enhanced adsorption of Zn-doped BiOI for FQs is due to its high specific surface area, coordination-based chemical adsorption, and surface electrostatic attraction, while its superior visible-light photodegradation performance is mainly ascribed to its strong redox ability, abundant surface oxygen vacancies, and enhanced photogenerated carrier separation efficiency.
开发高效、有效且大规模的处理方法来应对高风险新兴污染物（ECs）是环境修复领域日益增长的挑战。在此，提出了一种新颖的吸附分离与光降解再生并行耦合策略（parallel ASPR）；随后，设计了一种吸附光催化剂（Zn 掺杂 BiOI），以展示如何利用所提出的 ASPR 方案有效地从水中去除氟喹诺酮类药物（FQs）。与纯 BiOI 相比，合成过程中添加 Zn 对产物的形貌和结构有显著影响，导致 Zn 掺杂 BiOI 样品的比表面积增加了 5 倍，吸附容量增加了 32 倍，光电流强度增加了 20 倍。优化后的 Zn 掺杂 BiOI 样品对 FQs 具有优异的吸附效率，在 5 min 的吸附时间内，所有 6 种测试的 FQ 抗生素的去除率均超过 95%。然后，在后续可见光照射过程中，被吸附的污染物可以被有效降解，同时吸附剂可以同步再生，表现出优异的 ASPR 循环性能。通过材料特性、吸附模型、密度泛函理论计算和光生载流子分析等手段探究了快速吸附和光催化的机理。结果表明，Zn 掺杂 BiOI 对 FQs 的增强吸附归因于其高比表面积、配位化学吸附和表面静电吸引，而其优越的可见光光降解性能主要归因于其较强的氧化还原能力、丰富的表面氧空位和增强的光生载流子分离效率。
