硫化对零铁与三乙烯反应性的内在影响:一项DFT研究
Miroslav Brumovský1, Daniel Tunega1
1University of Natural Resources and Life Sciences, Vienna, Department of Forest- and Soil Sciences, Institute of Soil Research, Peter-Jordan-Straße 82, 1190 Vienna, Austria.
The journal of physical chemistry. C, Nanomaterials and interfaces
|November 8, 2023
概括
零价值铁 (ZVI) 的硫化最初阻碍了三乙烯 (TCE) 的脱. 然而,腐蚀引起的表面变化显示,硫化增强了ZVI的反应性和水处理的选择性.
科学领域:
- 环境化学环境化学
- 材料科学 材料科学 材料科学
- 表面化学 表面化学
背景情况:
- 对零价值铁 (ZVI),特别是纳米级ZVI (nZVI) 的硫化进行了探索,以改善水处理.
- 现有的研究集中在硫化对疏水性的影响上,忽视了它对污染物反应性的影响.
研究的目的:
- 研究硫化对ZVI表面与三乙烯 (TCE) 反应性的基本影响.
- 通过使用计算方法阐明硫化ZVI对TCE脱的反应机制.
主要方法:
- 使用密度函数理论 (DFT) 的计算.
- 模拟了各种ZVI表面模型,从原始Fe0到定期硫化Fe表面.
- 在这些表面上分析了TCE脱机制.
主要成果:
- 硫化本质上阻碍了ZVI的TCE脱,类似于催化中的硫中毒.
- 硫化对ZVI腐蚀产生积极影响,S位点显示出更高的反应性.
- 硫位点保护相邻的铁位点免受氧化,并增强直接电子转移的选择性.
结论:
- 硫化ZVI的反应性是内在抑制和腐蚀诱导的保护之间的平衡.
- 了解这些机制可以了解硫化ZVI对水处理中的特定污染物的选择性.
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