1-布吸附对UiO-66节点上的单金属离子体的二元化活性的影响
Laura Löbbert1, Saumil Chheda2,3, Jian Zheng4
1Department of Chemistry, Catalysis Research Center, Technical University Munich, 85747Garching, Germany.
Journal of the American Chemical Society
|January 4, 2023
概括
在基金属有机框架 (UiO-66) 上植入金属酸会产生二聚变的活性位点. 从Ni-UiO-66中去除水连接物显著增加了1-丁二聚变的催化活性.
科学领域:
- 材料科学
- 催化剂
- 纳米技术
背景情况:
- 金属有机框架 (MOF),特别是基于的UiO-66,提供可调节的催化结构.
- MOF中的缺陷点可以用金属来功能化,以创建定义良好的活跃中心.
- 二聚化是一个重要的工业过程,需要高效的催化剂.
研究的目的:
- 合成和表征UiO-66支持的金属催化剂 (M-UiO-66) 用于二元化.
- 研究金属标识和配体环境对催化活性的作用.
- 阐明这些新型催化场所的二化机制.
主要方法:
- M-UiO-66 (M = Ni,Co,Cu,Cr) 催化剂的合成和表征
- 交换和红外光谱以研究活性部位的结构.
- 热量测量和密度函数理论 (DFT) 分析1-布吸附和相互作用.
- 用于评估1-丁二聚化催化活性的动态研究.
主要成果:
- Ni-UiO-66显示出对1-布二聚化具有最高的催化活性.
- 从Ni-UiO-66中去除水连接物显著提高了1-布吸附和催化性能.
- 催化活性与不同金属位点的1-布吸附的吉布斯自由能量线性相关.
- DFT的计算支持了Cossee-Arlman机制,并确定了金属工厂作为活动中心.
结论:
- 用特定的金属离子功能化UiO-66提供高度活跃和选择性的二化位点.
- 水联体的存在或不存在对M-UiO-66催化剂的催化效率有重大影响.
- 由吸附热力学控制的金属中心活性位点决定了观察到的催化活动.
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