期刊
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
卷 140, 期 50, 页码 17643-17655出版社
AMER CHEMICAL SOC
DOI: 10.1021/jacs.8b09852
关键词
-
资金
- Air Force Office of Scientific Research Grant [FA9550-17-0198]
- National Science Foundation Graduate Research Fellowship [DGE-1122492]
Attaching molecular catalysts to metal and semiconductor electrodes is a promising approach to developing new catalytic electrodes with combined advantages of molecular and heterogeneous catalysts. However, the effect of the interfacial electric field on the stability, activity, and selectivity of the catalysts is often poorly understood due to the complexity of interfaces. In this work, we examine the strength of the interfacial field at the binding site of CO2 reduction catalysts including Re(S-2,2'-bipyridine)(CO)(3)Cl and Mn(S-2,2'-bipyridine)(CO)(3)Br immobilized on Au electrodes. The vibrational spectra are probed by sum frequency generation spectroscopy (SFG), showing pronounced potential-dependent frequency shifts of the carbonyl stretching modes. Calculations of SFG spectra and Stark tuning rates based on density functional theory allow for direct interpretation of the configurations of the catalysts bound to the surfaces and the influence of the interfacial electric field. We find that electrocatalysts supported on Au electrodes have tilt angles of about 65-75 degrees relative to the surface normal with one of the carbonyl ligands in direct contact with the surface. Large interfacial electric fields of 10(8)-10(9) V/m are determined through the analysis of experimental frequency shifts and theoretical Stark tuning rates of the symmetric CO stretching mode. These large electric fields thus significantly influence the CO2 binding site.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据