化物离子作为微孔晶体中的光电子供体
Satoru Matsuishi1, Katsuro Hayashi, Masahiro Hirano
1Frontier Collaborative Research Center, Tokyo Institute of Technology, Nagatsuta, Midori-ku, Yokohama 226-8503, Japan. satoru@lucid.msl.titech.ac.jp
Journal of the American Chemical Society
|September 8, 2005
概括
紫外线光将C12A7晶体中的化物离子解离,产生原子和被困电子. 这些电子在气消失后,有助于材料的电导率.
科学领域:
- 材料科学 材料科学 材料科学
- 固态物理 固态物理
- 摄影化学的使用
背景情况:
- 12CaO.7Al2O3 (C12A7) 晶体具有亚纳米尺寸的子,可以容纳离子.
- 在气氛中的热处理将化物离子 (H-) 引入这些子中.
- 了解被困物种在外部刺激下的行为对于材料开发至关重要.
研究的目的:
- 为了研究C12A7晶体中化离子的光解离.
- 描述由此产生的原子 (H0) 和被困电子 (F+中心).
- 探索被困电子对C12A7.7的电性质的影响.
主要方法:
- 电子磁共振 (EPR) 光谱技术被用来检测和分析原子和被困电子.
- 实验是在低温温度 (4K) 和紫外线照明 (λ ≈ 330nm) 下进行的.
- 为了观察产生的物种的稳定性,在300 K进行了回火研究.
主要成果:
- 用处理的C12A7的紫外线照明导致原子 (H0) 和被困电子 (F+中心) 在近1:1的比率下产生.
- 观察到的1:1比率为光解离反应提供了直接的证据:H- → H0 + e- (F+).
- 在300 K的化时,原子完全被消灭,而大约60%的被困电子仍然存在.
结论:
- 在C12A7中的化物离子可以通过紫外线有效地分解成原子和电子.
- 幸存的被困电子通过在子之间跳跃,有助于C12A7的电导率.
- 超细分的EPR光谱表明,原子被困在C12A7晶体结构中的间歇点.
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