Results
Title

Probing Interfacial Electronic and Catalytic Properties on Well‐Defined Surfaces by Using In Situ Raman Spectroscopy.

Authors

Wang, Ya‐Hao; Liang, Miao‐Miao; Zhang, Yue‐Jiao; Chen, Shu; Radjenovic, Petar; Zhang, Hua; Yang, Zhi‐Lin; Zhou, Xiao‐Shun; Tian, Zhong‐Qun; Li, Jian‐Feng

Abstract

Abstract: Heterogeneous metal interfaces play a key role in determining the mechanism and performance of catalysts. However, in situ characterization of such interfaces at the molecular level is challenging. Herein, two model interfaces, Pd and Pt overlayers on Au single crystals, were constructed. The electronic structures of these interfaces as well as effects of crystallographic orientation on them were analyzed by shell‐isolated nanoparticle‐enhanced Raman spectroscopy (SHINERS) using phenyl isocyanide (PIC) as a probe molecule. A clear red shift in the frequency of the C≡N stretch (νNC) was observed, which is consistent with X‐ray photoelectron spectroscopy (XPS) data and indicates that the ultrathin Pt and Pd layers donate their free electrons to the Au substrates. Furthermore, in situ electrochemical SHINERS studies showed that the electronic effects weaken Pt−C/Pd−C bonds, leading to improved surface activity towards CO electrooxidation.

Subjects

HETEROGENEOUS catalysis; REACTION mechanisms (Chemistry); SINGLE crystals; PLATINUM electrodes; RAMAN spectroscopy; ISOCYANIDES

Publication

Angewandte Chemie, 2018, Vol 130, Issue 35, p11427

ISSN

0044-8249

Publication type

Academic Journal

DOI

10.1002/ange.201805464