开发具有充分的光生电荷分离和强氧化还原能力的优良光催化剂系统来高效降解多种氟喹诺酮类 (FQ) 抗生素是至关重要的,但仍然是一个巨大的挑战。我们之前的工作验证了新型氧功能化 Ti 3 C 2 MXene/剥离蒙脱石 (Ti 3 C 2 /MMT ex ) 作为一种优异的助催化剂对提高单一半导体催化活性的显着影响。在此基础上,Bi 2 MoO 6颗粒/BiOBr 纳米片巧妙地锚定在多层 O 功能化的 Ti 3 C 2 /MMT ex上通过简单的两步微波辅助溶剂热过程以原位自组装的形式。代表性表征证实,由于 MMT ex 的引入,Ti 3 C 2 / MMT ex表现出化学稳定性并实现了从表面 F 端到 O 端的转变。此外,Ti 3 C 2 /MMT ex supporter 极大地减少了积累并改善了Bi 2 MoO 6 /BiOBr S 型异质结的形貌。广泛嵌入 Ti 3 C 2 /MMT ex上的 Bi 2 MoO 6 /BiOBr 片, BiOBr/Bi 2 MoO 6 /Ti 3 C 2 /MMT ex催化剂表现出非凡的珊瑚礁状结构,随后大量暴露出 BiOBr 的高活性 {0 0 1} 面。此外,由于肖特基/S型双异质结连接系统,在四元复合材料上形成的多个电子转移路径有效地促进了光生电荷载流子的分离,从而导致•O 2 -和•OH的生成增强。因此,多种 FQs 抗生素对 BiOBr/Bi 2 MoO 6 /Ti 3 C 2 /MMT的降解效率例如高达 90%,尤其是左氧氟沙星 (LEV),99% 的 LEV 可在 120 分钟内消除。此外,这种四元复合材料还表现出优异的可回收性和稳定性。值得注意的是,去甲基化和哌嗪开环主导了 LEV 降解途径,生成的中间体具有较低的毒性和生态风险。我们的研究进一步挖掘了 Ti 3 C 2 /MMT ex助催化剂在构建高效催化体系中的多重积极作用,并为设计稳定的非贵金属元/Bi 基半导体肖特基/S 型双异质结键提供了新策略具有紧凑接口接触的系统。
"点击查看英文标题和摘要"
Oxygen-functionalized Ti3C2 MXene/exfoliated montmorillonite supported S-scheme BiOBr/Bi2MoO6 heterostructures for efficient photocatalytic quinolone antibiotics degradation
Exploiting an excellent photocatalyst system with sufficient photogenerated charge separation and strong redox ability for efficient degradation of multiple fluoroquinolones (FQs) antibiotics was crucial but still a big challenge. The significant impacts of novel oxygen-functionalized Ti3C2 MXene/exfoliated montmorillonite (Ti3C2/MMTex) severed as a superior co-catalyst to boost the catalytic activity of single semiconductor was verified in our previous work. Based on that, the Bi2MoO6 particles/BiOBr nanosheets were ingeniously anchored onto multilayer O-functionalized Ti3C2/MMTex by the form of in-situ self-assembly via facile two-step microwave-assisted solvothermal process. Representative characterizations confirmed that Ti3C2/MMTex exhibited chemical stability and achieved transformation from surface F-terminal to O-terminal owing to the introduction of MMTex. Moreover, Ti3C2/MMTex supporter greatly decreased the accumulation and improved the morphology of Bi2MoO6/BiOBr S-scheme heterojunction. With extensive Bi2MoO6/BiOBr sheets embedding onto Ti3C2/MMTex, the quaternary BiOBr/Bi2MoO6/Ti3C2/MMTex catalyst displayed extraordinary coral reef-like structure, followed by abundantly exposing high-active {0 0 1} facets of BiOBr. Furthermore, owing to the Schottky/S-scheme double heterojunction linkage system, the multiple electrons transfer pathways formed over the quaternary composite effectively facilitated the separation of photogenerated charge carriers, thereby leading to the enhanced generation of •O2− and •OH. Hence, multiple FQs antibiotics degradation efficiency over BiOBr/Bi2MoO6/Ti3C2/MMTex all up to 90%, especially for levofloxacin (LEV), 99% LEV could be eliminated within 120 min. Besides, superior recyclability and stability were revealed in this quaternary composite. Notably, demethylation and piperazine ring-opening dominated LEV degradation pathway and the generated intermediates possessed lower toxicity and ecological risks. Our study further excavates multiple positive effects of Ti3C2/MMTex co-catalyst in constructing the efficient catalytic system, and supplies novelty tactics to engineer a stable non-noble meta/Bi-based semiconductor Schottky/S-scheme double heterojunction linkage system with compact interface contact.