通过合作电子再分配在MoVNbTeOx上形成氧基点
Yuanyuan Zhu, Peter V Sushko, Daniel Melzer1
1Department of Chemistry and Catalysis Research Center, Technische Universität München , Garching 85748, Germany.
Journal of the American Chemical Society
|August 22, 2017
概括
研究人员发现了一种新方法来促进MoVTeNb氧化物催化剂上的活性氧基位. 该过程通过在反应条件下动态重组催化剂表面来增强氧化脱.
科学领域:
- 催化剂
- 材料科学
- 表面化学
背景情况:
- 氧化脱 (AOD) 对于转化碳化合物至关重要.
- 开发高活性和稳定的AOD催化剂仍然是一个重大挑战.
- 对于AOD,MoVTeNb氧化物催化剂 (M1阶段) 是有前途的,但需要优化.
研究的目的:
- 在MoVTeNb氧化物 (M1阶段) 催化剂上增加催化活性氧基位的新途径.
- 阐明氧化脱过程中活性位点形成的机制.
- 展示一个新的策略来定制催化剂结构和动态,以加强活动.
主要方法:
- 在现场表征技术观察原子水平的动态变化.
- 密度函数理论 (DFT) 计算以建模电子结构和反应机制.
- 合成和催化测试MoVTeNb氧化物 (M1阶段) 催化剂
主要成果:
- 发现了一种新的途径, Te4+ 的减少和发射从M1晶体产生活跃的O- 基.
- 在这些新活跃点的形成过程中,催化剂框架的完整性得到维护.
- DFT计算证实了电子转移机制导致O-激素形成和合作效应.
结论:
- 在反应条件下,MoVTeNb氧化物催化剂的动态重组可以显著增强催化活性.
- 通过可控的 Te 降低来定制催化剂表面动态,为设计高活性 AOD 催化剂提供了新的途径.
- 了解原子级变化是优化异质催化剂的关键.
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