/对烯环氧化在Ag2O(111) 表面上的作用:一个DFT研究
Zean Xie1, Xin Wang1, Simeng Zhao1
1Institute of Catalysis for Energy and Environment, College of Chemistry and Chemical Engineering, Shenyang Normal University, Shenyang, 110034, P. R. China. songyyabc@nankai.edu.cn.
Physical chemistry chemical physics : PCCP
|February 6, 2025
概括
密度函数理论的计算揭示了在Ag2O表面上烯环氧化的双重机制. 用Cu或Au进行兴奋剂会影响反应途径和产品选择性,其中烯燃烧是主要的副产品.
科学领域:
- 不同质的催化剂.
- 表面科学是一门学科.
- 计算化学计算化学
背景情况:
- 烯环氧化对于生产烯氧化物 (PO) 至关重要.
- 广泛使用的是IB组金属催化剂,特别是基于银的催化剂.
- 了解反应机制和选择性是催化剂优化的关键.
研究的目的:
- 在Ag2O上研究烯环氧化,使用DFT与Cu或Au合.
- 阐明反应机制并确定影响产品选择性的因素.
- 为设计PO生产改进的IB集团催化剂提供见解.
主要方法:
- 旋转极化密度函数理论 (DFT) 用U校正进行计算.
- 双重反应途径的分析:酸剥离 (AHS) 和氧金属循环 (OMMP).
- 用于产品选择性预测的能量跨度模型分析.
主要成果:
- 鉴定出用于烯环氧化的双重机制 (AHS和OMMP).
- /兴奋剂增强了吸附剂活性,并影响了相邻的Osurf站点属性.
- 由于Osurf的基本性较低,Cu兴奋剂有利于OMMP路线;Au兴奋剂有利于AHS路线.
- 产品的选择性随着兴奋剂的使用而有显著的变化:阿克罗莱因是通过在所有表面上完全燃烧的主要副产品.
- 兴奋剂稍微增强了PO选择性,而au兴奋剂降低了它.
结论:
- 在Ag2O上的兴奋剂促进剂 (Cu,Au) 可以调整晶格氧的基本性和反应途径.
- 催化剂设计策略应侧重于调节氧的基本性,以优化PO产量.
- 对IB组催化剂的进一步研究可以导致更高效的烯环氧化工艺.
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