高度选择性,易于在化温度下将NO2降解为NO在预覆金上
Ming Pan1, Hyung Chul Ham, Wen-Yueh Yu
1Department of Chemical Engineering, Center for Nano and Molecular Science and Technology, Texas Materials Institute, Austin, Texas 78712-0231, United States.
Journal of the American Chemical Society
|December 13, 2012
概括
化金催化剂在低温下有效地将二氧化 (NO2) 降低到氧化 (NO). 这项研究揭示了黄金.
科学领域:
- 表面化学 表面化学
- 催化剂是一种催化剂.
- 材料科学 材料科学 材料科学
背景情况:
- 黄金催化剂是众所周知的化,但缺乏基本的表面化学研究.
- 减少二氧化 (NO2) 在各种化学过程中至关重要.
研究的目的:
- 为了研究在模型黄金催化剂上将NO2部分减少为NO.
- 了解黄金上的NO2化过程的基本表面化学.
主要方法:
- 在真空中以77K的温度进行实验调查.
- 密度函数理论 (DFT) 的计算.
- 反射吸收红外光谱学 (RAIRS).
主要成果:
- 100%的转化率和选择性可降低NO2到低于120K的NO.
- 确定HNO2和N2O3作为关键中间体.
- 中间体的形成取决于表面的度.
结论:
- 黄金对NO2化为NO的催化活性很高.
- 表面的度极大地影响了反应路径.
- 该研究提供了对黄金催化NO2减排的基本见解.
相关概念视频
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