School of Environmental Science and Engineering, Tianjin Engineering Research Center of Bio Gas/Oil Technology, Tianjin University, Tianjin 300072, China.
School of Environmental Science and Engineering, Tianjin Engineering Research Center of Bio Gas/Oil Technology, Tianjin University, Tianjin 300072, China.
Sci Total Environ. 2021 Mar 20;761:143268. doi: 10.1016/j.scitotenv.2020.143268. Epub 2020 Oct 27.
A valence-state heterojunction MnO/γ-MnOOH was synthesized for norfloxacin (NOR) degradation under concurrent visible light and magnetic field. The charge carriers could transfer between the valence state components facilely, inhibiting recombination of photo-induced electron-holes significantly. Efficient NOR degradation by MnO/γ-MnOOH was realized at 98.8% (rate constant of 0.0720 min) within 60 min under magnetic field assisted visible light. In neutral media, the positively charged NOR and negatively charged MnO/γ-MnOOH would arrange in an oriented manner in the presence of magnetic field, providing more active sites for NOR during photocatalysis. Moreover, the opposite Lorentz forces contributed to the attractive interactions between NOR and MnO/γ-MnOOH, accelerating NOR degradation with lower active energy. Quenching experiment showed that ∙O and h played dominant roles in NOR degradation. Attractively, this study shed new lights on an innovative strategy of magnetic field assisted photocatalysis for refractory contaminants remediation from water.
MnO/γ-MnOOH 价态异质结的合成及其在可见光和磁场协同作用下对诺氟沙星（NOR）的降解。价态组分之间的载流子可以容易地转移，显著抑制光生电子-空穴的复合。在磁场辅助可见光下，MnO/γ-MnOOH 在 60 分钟内实现了高效的 NOR 降解，降解率为 98.8%（速率常数为 0.0720 min）。在中性介质中，带正电荷的 NOR 和带负电荷的 MnO/γ-MnOOH 在磁场的存在下会排列成定向方式，为光催化过程中的 NOR 提供更多的活性位点。此外，相反的洛伦兹力有助于 NOR 和 MnO/γ-MnOOH 之间的吸引力相互作用，从而以较低的活性能加速 NOR 的降解。猝灭实验表明，∙O 和 h 在 NOR 降解中起主导作用。引人注目的是，本研究为磁场辅助光催化从水中修复难降解污染物提供了一种创新策略。
