调整以Pd为基础的异质催化剂的化化学,通过引入同质类联体
Jianghao Zhang1,2, Wenda Hu1,3, Binbin Qian4,5
1The Gene & Linda Voiland School of Chemical Engineering and Bioengineering, Washington State University, Pullman, WA, 99164, USA.
Nature communications
|July 4, 2023
概括
贵金属催化剂可以用配体进行修改,以选择性地控制化反应. 这种方法可以提高催化剂的选择性,用于诸如素水处理和乙烯化等应用.
科学领域:
- 催化剂是一种催化剂.
- 材料科学 材料科学 材料科学
- 化学工程是化学工程的重要组成部分.
背景情况:
- 像 (Pd) 这样的贵金属对于水处理催化剂中的激活至关重要.
- 然而,它们可能会引起不良的副作用,如深度化,降低整体选择性.
- 在保持催化功能的同时,开发选择性抑制副作用的方法至关重要.
研究的目的:
- 提出一种用基类型连接体修改异质 (Pd) 催化剂的策略.
- 通过形成同质的Pd-烯金属循环结构来实现选择性解和化.
- 提高Pd基催化剂在水处理和化反应中的选择性.
主要方法:
- 用基型碳联体剂合的铁 (Pd-Fe) 催化剂的修改.
- 在异质催化剂表面上形成Pd-烯金属循环结构.
- 研究连接体的电子捐赠效应,以创造富含电子的Pd环境.
主要成果:
- 修改后的Pd-Fe催化剂表现出富含电子的Pd,减弱了与不和碳的相互作用,并控制了化化学.
- 保持了高的H2激活,激活的H转移到Fe,用于C-O键裂解或对Pd的反应.
- 修改后的催化剂在二乙烯 (DPE) 水处理中具有>90%的选择性,在乙烯化中具有>90%的乙烯选择性,其性能优于裸体Pd-Fe (<50%的选择性).
结论:
- 修改Pd催化剂用基类型连接体提供了一种可行的方法,可以选择性地抑制副作用.
- 在异质催化剂上模仿同质类似物为选择性水处理催化剂的受控合成提供了一条途径.
- 这一策略有效地提高了关键化学转换的选择性,如素模型化合物水处理和乙烯化.
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