甲醇和水在TiO2上逐步的光催化解离子 (二氧化)
Qing Guo1, Chenbiao Xu, Zefeng Ren
1State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, 457 Zhongshan Road, Dalian 116023, Liaoning, P. R. China.
Journal of the American Chemical Society
|July 17, 2012
概括
这项研究表明,二氧化 (TiO(2) 有效光催化甲醇 (CD(3) OH) 解离,但没有水 (H(2) O) 分离. 由于反向反应的高能量障碍,TiO(2)(110) 上的甲醇解离得到了青.
科学领域:
- 表面科学是一门科学.
- 光催化作用的光催化
- 材料化学 材料化学
背景情况:
- 二氧化 (TiO(2) 是一个广泛研究的光催化剂.
- 了解甲醇和水对TiO2的表面反应对于催化应用至关重要.
- 在各种条件下研究了TiO(2)(110) 对甲醇和水的光催化活性.
研究的目的:
- 为了研究TiO2表面上部分化甲醇 (CD3OH) 和水 (H2O) 的光催化.
- 为了阐明反应路径和识别光催化产品.
- 了解影响甲醇解离与水分裂效率的因素.
主要方法:
- 用一种新开发的光催化装置进行实验.
- 采用400纳米的光用于光催化.
- 将实验发现与理论计算结合起来,分析反应机制.
主要成果:
- 从CD(3) OH光催化过程中,在Ti(5c) 位点上明显检测到CD(2) O,在桥接氧 (BBO) 位点上检测到H/D原子.
- 在实验条件下没有发现H(2) O光催化物的证据.
- 观察到CD(3) OH的逐步解离,O-H解离之前的C-D解离.
结论:
- 由于C-D重组的高反向屏障和易于CD(2) O脱离,CD(3) OH在TiO(2) ((110) 上的光催化分解是高效的.
- 有效的光催化水分裂是通过容易的O-H重组在H(2) O解离后被抑制的.
- TiO(2)(110) 显示了选择性的光催化活性,有利于甲醇解离而不是水分裂.
相关概念视频
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