在高效的基半化中,在基结合的共价有机框架内构建超小的Pd集群
Xujiao Ma1, Zhong Zhang1, Die Zhao2
1School of Chemistry, Dalian University of Technology, Dalian, 116024, China.
在基结合的COF中空间封闭会产生超小的金属集群,以实现高效的基半化. 这种新的催化剂设计克服了活动选择性权衡,提高了化性能.
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:
- 在多孔材料中限制金属物种优化化.
- 仅专注于金属的电子调制限制了催化剂设计.
- 开发新的催化剂设计策略对于提高性能至关重要.
研究的目的:
- 开发一种空间限制策略,用于在基结合的共价有机框架 (COF) 中构建超小金属集群.
- 在选择性化反应中研究这些金属-COF复合物的催化性能.
- 了解涉及金属集群和有机功能组的联合催化机制.
主要方法:
- 使用空间限制策略合成嵌入金属的酸结合COFs (M@TpPa-NO2).
- 测试Pd@TpPa-NO2的催化活性和选择性,以测试其化.
- 在机械研究中使用现场扩散反射红外里埃变换光谱 (in situ DRIFTS).
- 使用密度函数理论 (DFT) 计算来阐明反应路径.
主要成果:
- Pd@TpPa-NO2表现出高活性 (TOF = 13756 h−1) 和选择性 (94%) 在25 °C和1 bar H2.2 的乙烯半化.
- 观察到共催化,在Pd集群上发生H2解离,从基组转移H原子.
- 烯从TpPa-NO2支中轻松脱落,有助于高选择性.
结论:
- 在基结合COF中的空间限制使得高效的超小金属集群催化剂的构建成为可能.
- Pd@TpPa-NO2系统有效地克服了选择性化中的活动选择性权衡.
- 这种方法为设计用于化反应的先进催化剂提供了新的途径.
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