在Pd@UiO-66上的直接CO化中选择性控制:Pd位置很重要
Shuaishuai Hu1, Chenfan Xie1, Yu-Ping Xu2,3
1Hefei National Research Center for Physical Sciences at the Microscale, Department of Chemistry, University of Science and Technology of China, Hefei, Anhui, 230026, P. R. China.
Angewandte Chemie (International ed. in English)
|September 1, 2023
概括
这项研究引入了一种新的方法,用于控制一氧化碳化中的纳米粒子选择性. 通过将嵌在金属有机框架中,研究人员实现了二甲基碳酸盐生产的高选择性.
科学领域:
- 材料科学 材料科学 材料科学
- 催化剂是一种催化剂.
- 纳米技术纳米技术
背景情况:
- 控制纳米粒子 (Pd NP) 催化在直接一氧化碳 (CO) 化中的选择性是一个重大挑战.
- 现有的方法通常会产生二甲基酸盐 (DMO) 或二甲基碳酸盐 (DMC) 的混合物.
研究的目的:
- 开发一种战略,以实现高选择性对二甲基碳酸盐 (DMC) 在使用纳米颗粒直接CO化反应.
- 为了研究纳米粒子在金属有机框架 (MOFs) 内的位置对催化选择性的影响.
主要方法:
- 将纳米颗粒 (PdNP) 纳入异构金属有机框架 (MOF),特别是UiO-66-X (X=-H, -NO2, -NH2),以创建Pd@UiO-66-X.
- 对MOF的催化性能与传统支持的Pd NP进行比较 (Pd/UiO-66).
- 使用实验数据和密度函数理论 (DFT) 计算来理解结构-活动关系.
主要成果:
- Pd@UiO-66-X催化剂对二甲基碳酸盐 (DMC) 显示出意想不到的高选择性 (高达99%).
- 相比之下,Pd/UiO-66催化剂对二甲基酸盐 (DMO) 具有很高的选择性 (89%),与之前的研究结果一致.
- DFT计算和实验结果表明,Pd@UiO-66和Pd/UiO-66中的Zr-oxo集群和Pd NP之间的独特微环境和接口区域决定了观察到的选择性差异.
结论:
- 纳米颗粒在MOF内部或表面的位置显著影响其在直接CO化中的选择性.
- 这项工作提出了一种前所未有的方法,用于使用Pd NP进行DMC生产,这种转换以前仅限于Pd (II) 催化剂.
- 这些发现为设计高度选择性的异质催化剂开辟了新的途径,通过控制金属纳米粒子在MOF结构中的集成.
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