在 TiO2 解剖酶 (101) 上逐步减少氧气
Martin Setvin1, Ulrich Aschauer2, Jan Hulva1
1TU Wien , Wiedner Hauptstrasse 8-10/134, 1040 Vienna, Austria.
Journal of the American Chemical Society
|July 5, 2016
概括
在减少的二氧化 (TiO2) 解酶表面上研究氧和水,发现水解离形成稳定的基 (OH) 组. 捐赠剂可以降低氧降低反应的激活障碍.
科学领域:
- 表面科学
- 材料化学
- 物理化学
背景情况:
- 二氧化 (TiO2) 是光催化和能源应用中的关键材料.
- 了解TiO2的表面反应是优化其性能的关键.
- 氧 (O2) 和水 (H2O) 在TiO2表面的相互作用对许多催化过程至关重要.
研究的目的:
- 在减少的TiO2解酶 (101) 表面上阐明共吸收的O2和H2O之间的反应路径.
- 确定稳定的反应产物和中间体.
- 研究表面电子特性和剂在反应动力学中的作用.
主要方法:
- 扫描道显微镜 (STM) 用于原子层面成像.
- 密度函数理论 (DFT) 用于电子结构和反应屏障计算.
- 用温度编程的脱吸 (TPD) 来研究脱吸动力学.
- 用于表面化学状态分析的X射线光电子光谱 (XPS).
主要成果:
- 水在解酶 (101) 表面上分子吸附.
- 与O2的反应导致水分离,形成终端基 (OH) 组作为稳定的产物.
- 已被确定为转移稳定的中间物质的氧化物 (OOH).
- 反应范围取决于TiO2表面的电子转移.
- 激活障碍受到电子可用性和表面兴奋剂的影响.
结论:
- 终端OH组是降解解酶的O2-H2O反应的稳定终点.
- 表面电子的可用性决定了水解离反应的进展.
- 在TiO2中给予供体可以显著降低氧降低的激活障碍,增强催化活性.
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