文献类型：期刊文献

英文题名：A Single-Molecule-Level Mechanistic Study of Pd-Catalyzed and Cu-Catalyzed Homocoupling of Aryl Bromide on an Au(111) Surface

作者：Adisoejoso, Jinne[1];Lin, Tao[1];Shang, Xue Song[2,3];Shi, Ke Ji[2,3];Gupta, Aditi[1];Liu, Pei Nian[2,3];Lin, Nian[1]

机构：[1]Hong Kong Univ Sci & Technol, Dept Phys, Hong Kong, Hong Kong, Peoples R China;[2]E China Univ Sci & Technol, Shanghai Key Lab Funct Mat Chem, Shanghai 200237, Peoples R China;[3]E China Univ Sci & Technol, Inst Fine Chem, Shanghai 200237, Peoples R China

年份：2014

卷号：20

期号：14

起止页码：4111

外文期刊名：CHEMISTRY-A EUROPEAN JOURNAL

收录：;EI(收录号：20141517550237);WOS:【SCI-EXPANDED(收录号:WOS:000333447200033)】；

基金：This work was supported financially by the Hong Kong Research Grants Council (project no. 602712), the National Natural Science Foundation of China (project nos. 21172069 and 21190033), the Innovation Program of Shanghai Municipal Education Commission (project no. 12ZZ050), and the Fundamental Research Funds for the Central Universities.

语种：英文

外文关键词：copper; kinetics; palladium; scanning probe microscopy; surface chemistry

摘要：On-surface Pd- and Cu-catalyzed CC coupling reactions between phenyl bromide functionalized porphyrin derivatives on an Au(111) surface have been investigated under ultra-high vacuum conditions by using scanning tunneling microscopy and kinetic Monte Carlo simulations. We monitored the isothermal reaction kinetics by allowing the reaction to proceed at different temperatures. We discovered that the reactions catalyzed by Pd or Cu can be described as a two-phase process that involves an initial activation followed by CC bond formation. However, the distinctive reaction kinetics and the CC bond-formation yield associated with the two catalysts account for the different reaction mechanisms: the initial activation phase is the rate-limiting step for the Cu-catalyzed reaction at all temperatures tested, whereas the later phase of CC formation is the rate-limiting step for the Pd-catalyzed reaction at high temperature. Analysis of rate constants of the Pd-catalyzed reactions allowed us to determine its activation energy as (0.41 +/- 0.03)eV.