通过使用过渡方法对平衡实验的控制方法来理解反应网络
Yixiao Wang1, Jin Qian2,3, Zongtang Fang1
1Biological and Chemical Science and Engineering Department, Idaho National Laboratory, Idaho Falls, Idaho 83415, United States.
Journal of the American Chemical Society
|July 19, 2021
概括
这项研究将低压脉冲响应实验与量子力学计算相结合, 研究催化过程. 该方法揭示了铁和催化剂的氨合成和分解中的关键表面反应步骤和中间寿命.
科学领域:
- 不同质的催化
- 表面科学
- 计算化学
背景情况:
- 了解异质催化过程对于化学合成至关重要.
- 传统的方法往往缺乏对表面反应机制的详细见解.
- 氨的合成和分解是工业上重要的反应.
研究的目的:
- 开发和展示一种结合实验和理论方法来研究气体/固体的催化反应.
- 阐明单个表面反应步骤在氨合成和分解中的作用.
- 确定模型催化剂的表面反应路径和中间寿命.
主要方法:
- 对多晶铁和进行了低压时间产品分析 (TAP) 脉冲响应实验.
- 基于量子力学 (QM) 的计算用于确定相关金属面 (Fe-BCC,Co-FCC) 的反应自由能量.
- 控制反应物的脉冲 (氨,) 和不同的延迟时间被用来探测反应机制和平衡的方法.
主要成果:
- 综合方法成功提供了表面反应步骤的详细信息.
- 形成障碍被确定为控制表面中间度的关键因素.
- 为铁和催化剂确定了关键反应中间体的表面寿命.
结论:
- 开发的实验/理论方法对于解剖复杂的催化反应机制是有效的.
- 从单金属催化剂获得的洞察力被成功地应用于解释双金属CoFe催化剂的结果.
- 这种方法为理解和设计异质催化剂提供了强大的工具.
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