氧气吸附和激活控制普通铁氧化多态体的光化学活性,在可见光下调解氧化在可见光下降解
Ting Chang1, Jing Sun1, Shiwen Li2
1College of Quality and Technical Supervision, Hebei University, Baoding 071002, China.
Journal of colloid and interface science
|January 1, 2025
概括
铁氧化矿物质在光下产生反应性氧物种 (ROSs),这对于降解有机污染物,如氧环素 (OTC) 至关重要. 超氧化基 (O2•−) 主导着OTC降解,受矿物质结构和氧气激活的影响.
科学领域:
- 环境化学环境化学
- 材料科学 材料科学 材料科学
- 光催化作用的光催化
背景情况:
- 半导体天然矿物通过产生反应性氧物种 (ROSs) 表现出光化学活性,影响有机污染物的降解.
- 铁氧化在不同的环境条件下存在于各种多态 (哥,阿加尼,勒皮多克罗,费洛西).
- 铁氧化多态体之间的光活性差异及其在污染物降解中的作用仍然不完全理解.
研究的目的:
- 阐明普通铁氧化水氧化物多态体光诱导ROS生成的机制.
- 调查这些多态体对氧化环素 (OTC) 的中介降解.
- 将ROS生成,特别是超氧化激素与OTC降解率相关联,并确定影响因素.
主要方法:
- 四种铁氧化多态 (α-, β-, γ-, δ-FeOOH) 的可见光照射.
- 生成的ROS的量化 (超氧化基,基,H2O2).
- 监测氧化四环素 (OTC) 降解率和与ROS度的相关性.
主要成果:
- 在可见光下,所有铁氧化多态都产生了超氧化基 (O2•−),基 (•OH) 和H2O2.
- 超氧化基 (O2•−) 被确定为OTC降解中占主导地位的ROS,其度在多态体之间有显著差异.
- 场外降解率与O2•−度有很强的正相关性,主要是由于O2在矿物表面的吸附和激活.
结论:
- 铁氧化多态体在降解OTC中的光化学活性主要由氧气的吸附和激活控制.
- 矿物质结构,结晶性和表面氧空缺影响Fe2+生成,影响通过芬顿反应产生OH.
- 了解这些机制,可以在有机污染物的环境修复中有针对性地应用氧化氧化铁.
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