Department of Civil and Environmental Engineering, The Hong Kong University of Science and Technology, Hong Kong, China.
Key Laboratory for Advanced Materials, Centre for Computational Chemistry and Research Institute of Industrial Catalysis, School of Chemistry and Molecular Engineering, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, China.
J Hazard Mater. 2021 Aug 15;416:125891. doi: 10.1016/j.jhazmat.2021.125891. Epub 2021 Apr 16.
CoP nanoparticle-loaded N-doped graphitic CN nanosheets (CoP/N-g-CN) were fabricated via a facile three-step method to degrade pharmaceuticals and personal care products (PPCPs) via a visible-light-driven (VLD) peroxymonosulfate (PMS) activation system. 2 ppm carbamazepine (CBZ) can be removed completely within 10 min by the VLD-PMS system with a kinetic constant of k = 0.29128 min, as 25.8 times compared to that under dark conditions (k = 0.01128 min). The experimental and theoretical results showed that the doped graphitic N atoms could modulate the electronic properties of the g-CN nanosheets. Subsequently, the Density Functional Theory (DFT) explained that CoP showed preference to bonding with the nitrogen atoms involved in the newly formed N˭N bond, and the Co‒N bond dramatically enhanced the transfer of photo-generated electrons from the N-g-CN nanosheets. Electron paramagnetic resonance (EPR) tests show that singlet oxygen (O) plays a leading role in this case. Moreover, PMS molecules are also tended to be absorbed onto the electron-deficient carbon atoms near the newly formed N˭N bonds for PMS reduction, synergistically enhancing the degradation efficiency for CBZ and benzophenone-3 (BZP). The newly established VLD-PMS activation system was shown to treat the actual sewage in Hong Kong sewage treatment plants (STPs) very well. This work supplements the fundamental theory of radical and non-radical pathways in the sulfate radical (SO)-based advanced oxidation process (SR-AOP) for environmental cleanup purposes.
CoP 纳米颗粒负载氮掺杂石墨相氮化碳纳米片（CoP/N-g-CN）通过简便的三步法制备，用于通过可见光驱动（VLD）过一硫酸盐（PMS）活化系统降解药物和个人护理产品（PPCPs）。在 VLD-PMS 系统中，2ppm 的卡马西平（CBZ）可以在 10min 内完全去除，动力学常数 k 为 0.29128min，比暗条件下（k=0.01128min）快 25.8 倍。实验和理论结果表明，掺杂的石墨 N 原子可以调节 g-CN 纳米片的电子性质。随后，密度泛函理论（DFT）解释说，CoP 优先与新形成的 N≡N 键中涉及的氮原子结合，并且 Co-N 键极大地促进了光生电子从 N-g-CN 纳米片的转移。电子顺磁共振（EPR）测试表明，单线态氧（O）在此过程中起主要作用。此外，PMS 分子也倾向于被吸附到新形成的 N≡N 键附近的电子缺碳原子上以还原 PMS，协同增强 CBZ 和二苯甲酮-3（BZP）的降解效率。所建立的新型 VLD-PMS 活化系统在处理香港污水处理厂（STP）中的实际污水方面表现出色。这项工作补充了基于硫酸盐的高级氧化工艺（SR-AOP）中自由基和非自由基途径的基本理论，用于环境清理目的。
