期刊
SCIENCE OF THE TOTAL ENVIRONMENT
卷 722, 期 -, 页码 -出版社
ELSEVIER
DOI: 10.1016/j.scitotenv.2020.137853
关键词
Electro-Fenton; Nitrogen-doped cathode; Oxygen reduction reaction; Density functional theory
资金
- National Key Research and Development Plan [2016YFC0401102]
- National Science and Technology Major Projects of the Ministry of Environmental Protection of China [2019YFD1100204]
In this work, nitrogen-doped cathodes for high H2O2 production and sulfathiazole (STZ) degradation in electro-Fenton (EF) systems were prepared by the carbonization of three carbon/nitrogen-enriched precursors. Among the cathodes elaborated from different precursors, the one using 1h-1,2,4-triazole-3,5-diamine as the precursor showed the best oxygen reduction reaction (ORR) ability with the normalized H2O2 accumulation of 9.49 +/- 0.03 mg L-1 h(-1) cm(-2) compared to the other two N-containing cathodes. The enhanced H2O2 accumulation was attributed to the high electroactive surface area and pyrrolic N (60.45%) content. Regarding reactive oxygen species in the absence of Fe2+, aside from the H2O2, center dot O-2(-) and O-1(2) were identified using spectroscopic techniques and chemical probes. As a result, a degradation and mineralization efficiency of 98.25 +/- 0.14% and 70.57 +/- 0.27% of STZ were attained in the 180-min treatment, mainly coming fromthe homogeneous center dot OH from classical Fenton, anodic center dot OH on BDD anode and direct/indirect oxidation of center dot O-2(-) and O-1(2). In addition, the plausible degradation pathway of STZ was proposed based on the density functional theory (DFT) combined with experimental data derived by ultra-performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS). The frontier orbital theory and Fukui function theoretically suggested the vulnerable sites of STZ for different active species including center dot OH, center dot O-2(-) and O-1(2). This study provides a new strategy for improving the ORR process and analyzing the generation and conversion of reactive oxygen species in the EF process. (C) 2020 Elsevier B.V. All rights reserved.
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