期刊
JOURNAL OF HAZARDOUS MATERIALS
卷 416, 期 -, 页码 -出版社
ELSEVIER
DOI: 10.1016/j.jhazmat.2021.125936
关键词
Graphitic carbon nitride; Single-atom Barium; Photosensitation-like; First excited state; Valence excitation mode
资金
- National Natural Science Foundation of China [51908082, 41907107]
- Fundamental Research Funds for the Central Universities [2020CDJYGHS002]
- Large Instruments Open Foundation of Chongqing University [202003150090, 202003150089]
The study found that single-atom Barium (Ba) embedded g-C3N4 enhances the photocatalytic activity for carbamazepine (CBZ) and diclofenac (DCF) degradation by different mechanisms. CBZ degrades through a typical photocatalysis mechanism, while DCF degrades via a photosensitization-like process. Due to the different degradation mechanisms, the effects of pH, co-existed anions, and water matrix are also different. The photosensitization-like mechanism of DCF shows higher anti-interference capacity in real water as it does not rely on photo-generated holes mediated oxidation.
This study reports the different degradation mechanisms of carbamazepine (CBZ) and diclofenac (DCF) by singleatom Barium (Ba) embedded g-C3N4. Single-atom Ba is anchored onto g-C3N4 by forming ionic bond with triazine ring, thus greatly enhances the photocatalytic activity with an atom ratio of 1.78%. CBZ undergoes a typical photocatalysis mechanism, while DCF is degraded via a photosensitization-like process, which does not need band gap excitation of photocatalyst. By means of Density Functional Theory (DFT) calculation, the selectivity is found to be related with the different valence excitation modes of CBZ and DCF. Specifically, CBZ undergoes a local excitation, which does not obviously affect molecular configuration. In contrast, DCF undergoes a charge transfer excitation, which significantly changes the reactive sites distribution and facilitates photosensitizationlike degradation. Due to the different degradation mechanism, the effects of pH, co-existed anions, and water matrix are also different. Since photosensitization-like mechanism does not rely on photo-generated holes mediated oxidation, the degradation efficient of DCF shows higher anti-interference capacity in real water.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据