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Updated: Jul 7, 2026
07:03
Low-energy Cathodoluminescence for (Oxy)Nitride Phosphors
Published on: November 15, 2016
在可见光下化二氧化的光活性起源
Stefano Livraghi1, Maria Cristina Paganini, Elio Giamello
1Dipartimento di Chimica IFM, Università di Torino and NIS Center of Excellence, Via P. Giuria 7, 10125 Torino, Italy.
Journal of the American Chemical Society
|December 7, 2006
概括
二氧化 (N-TiO2) 由于单原子杂质而表现出可见光光催化作用. 这些中心在辐射下促进电子转移,驱动光催化过程.
科学领域:
- 材料科学 材料科学 材料科学
- 光催化作用的光催化
- 固态化学 固态化学
背景情况:
- 二氧化 (TiO2) 是一个广泛研究的光催化剂,但其应用受到其宽带间隙的限制,需要紫外线光激活.
- 可见光响应光催化剂对于扩大太阳能应用至关重要.
- 兴奋剂是一种常见的策略,用于缩小TiO2的带隙,从而实现可见光活性.
研究的目的:
- 研究二氧化 (N-TiO2) 的电子结构和可见光光催化机制.
- 描述TiO2网格中单原子杂质的性质和行为.
- 为了阐明在可见光照射下N-TiO2中发生的电子转移过程.
主要方法:
- 结合实验和理论方法.
- 电子偏磁共振 (EPR) 光谱学.电子偏磁共振 (EPR) 光谱学.
- 密度函数理论 (DFT) 计算 (理论方法暗示).
主要成果:
- N-TiO2 含有单原子杂质,形成二磁性 (Nb-) 和二磁性 (Nb*) 中心.
- 这些中心在TiO2带间隙中产生局部状态.
- 辐射下的EPR光谱证实,Nb中心吸收可见光,将电子从局部状态提升到导电带或表面清理器.
- 丰富的Nb-和Nb*中心受材料的氧化状态的影响.
结论:
- TiO2中的单原子杂质是其可见光光催化活性的原因.
- 该研究提供了与N杂质相关的电子状态的详细描述.
- 在可见光下首次建立了N-TiO2中电子促进和转移的机械图像.
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