Scanning tunneling microscopy, Fourier transform infrared reflection-absorption spectroscopy, and X-ray photoelectron spectroscopy of thiourea adsorption from aqueous solutions on silver (111)

被引：17

作者：

Brunetti, V

Blum, B

Salvarezza, RC

Arvia, AJ

Schilardi, PL

Cuesta, A

Gayone, JE

Zampieri, G

机构：

[1] Natl Univ La Plata, CONICET, INIFTA, RA-1900 La Plata, Argentina

[2] CSIC, Inst Quim Fis Rocasolano, E-28006 Madrid, Spain

[3] Comis Nacl Energia Atom, Ctr Atom Bariloche, RA-8400 San Carlos De Bariloche, Rio Negro, Argentina

[4] Univ Nacl Cuyo, RA-8400 San Carlos De Bariloche, Rio Negro, Argentina

来源：

JOURNAL OF PHYSICAL CHEMISTRY B | 2002年 / 106卷 / 38期

关键词：

D O I：

10.1021/jp0209695

中图分类号：

O64 [物理化学（理论化学）、化学物理学];

学科分类号：

070304 ; 081704 ;

摘要：

Thiourea (TU) adsorption on Ag(111) from aqueous solutions was investigated by in situ scanning tunneling microscopy operating under potential control. Hexagonal arrangements with d = 0.44, 0.38, and 0.33 nm were imaged at potentials close to -1.2 V (vs SCE), where conjugated voltammetric current peaks are observed. The analysis of in situ Fourier transform infrared reflection-absorption spectra (FT-IRRAS) shows that these current peaks mainly involve electroadsorption/electrodesorption of TU on the Ag(111) surface. Data from ex situ X-ray photolectron spectroscopy of TU-covered Ag(111) closely resemble those obtained for adsorbed alkanethiols on the same substrate, suggesting that the canonical form of TU is the species adsorbed from aqueous solutions. Experimental evidence of TU degradation into other sulfur species is also observed.

引用

页码：9831 / 9838

页数：8

共 64 条

[1] In situ STM and electrochemical investigation of sulfur oxidative underpotential deposition on Ag(111) [J].