在有氧缺陷的固态Keggin型基酸上进行氧化催化
Satoshi Ishikawa1, Takuji Ikeda2, Maki Koutani1
1Department of Material and Life Chemistry, Faculty of Engineering, Kanagawa University, 3-27-1, Rokkakubashi, Kanagawa-ku, Yokohama 221-8686, Japan.
Journal of the American Chemical Society
|April 19, 2022
概括
经过皮里丁处理的基酸 (PyPMo-HT) 对选择性氧化具有增强的催化活性. 这源于通过电子转移形成的电友性氧物种,改善了工业聚氧甲酸催化中的甲酸产量.
科学领域:
- 不同质的催化剂.
- 材料科学 材料科学 材料科学
- 无机化学 无机化学
背景情况:
- 凯金类型的基酸 (PMo12O40) 衍生物在气相氧化催化中表现有前途.
- 像PyPMo-HT这样的修饰聚氧甲酸盐 (POMs) 中催化活性的确切起源需要详细的研究.
- 了解结构-活动关系对于优化基于POM的工业催化剂至关重要.
研究的目的:
- 在热处理后阐明胺处理的聚酸 (PyPMo-HT) 的晶体结构.
- 为了确定负责观察到的氧化活动的催化活性物种.
- 在选择性氧化反应中,将结构转变与增强的催化性能相关联.
主要方法:
- 通过在惰性气体流下将酸与化进行热处理,合成PyPMo-HT.
- 确定PyPMo-HT的晶体结构.
- 研究涉及分子氧气和烯和甲烯的催化氧化反应机制.
主要成果:
- PyPMo-HT 形成了一个一维的Keggin 单元和酸的数组,具有特定的HPy/Keggin 比率.
- 在转换过程中去除氧气会导致Mo原子的局部电子密度,从而促进电子转移.
- 电友氧物种形成桥梁Keggin单元,作为选择性氧化活性位点,产生高甲酸.
结论:
- 通过皮里丁处理对基酸的结构修饰产生活性电友性氧物种.
- 与原始化合物相比,PyPMo-HT对甲甲烯氧化具有优越的催化活性.
- 这项研究加深了对工业氧化过程中基于聚氧甲酸盐的催化剂的理解.
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