Potential dependent thiocyanate adsorption on gold electrodes: a comparison study between SERS and SHINERS

Potential dependent adsorption of target molecules on electrode surface has long been analyzed by several analytical techniques at the electrochemical interfaces. Here, the adsorption of thiocyanate (SCN−) on gold electrodes [Au (111) and Au (poly)] is investigated by electrochemical shell isolated...

Full description

Saved in:
Bibliographic Details
Published in:Journal of Raman spectroscopy 2016-10, Vol.47 (10), p.1207-1212
Main Authors: Cabello, Gema, Chen, Xue-Jiao, Panneerselvam, Rajapandiyan, Tian, Zhong-Qun
Format: Article
Language:English
Subjects:
Adsorption
Cyanates
Electrodes
Gold
gold single-crystal
Mathematical analysis
Raman spectroscopy
SERS
SHINERS
spectroelectrochemistry
Spectrum analysis
Surface chemistry
thiocyanate
Thiocyanates
Citations: Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Potential dependent adsorption of target molecules on electrode surface has long been analyzed by several analytical techniques at the electrochemical interfaces. Here, the adsorption of thiocyanate (SCN−) on gold electrodes [Au (111) and Au (poly)] is investigated by electrochemical shell isolated nanoparticle‐enhanced Raman spectroscopy (EC‐SHINERS) and surface‐enhanced Raman spectroscopy. Based on the experimental observation, C − N stretching mode of N‐bound SCN− can be observed around 2080 cm−1 throughout the whole potential range. The band corresponding to νC−N of S‐bound SCN− appears as a shoulder at more negative potentials, and as a well‐defined band are more positive potentials. However, the overlapped bands provoke a negative shift in the frequency of S‐bound thiocyanate. Therefore, a change in the calculated Stark slope is observed. Interestingly, SHINERS has been employed to demonstrate the thiocyanate orientation and its effect on Raman spectra. Our results widen the opportunities of SHINERS to unravel the potential‐dependent adsorption behavior of target molecules on single‐crystal electrode surfaces. Copyright © 2016 John Wiley & Sons, Ltd. SCN adsorption on Au(111) electrodes was studied by shell‐isolated nanoparticle‐enhanced Raman spectroscopy. The band at 2165 cm−1 corresponds to cyanate from the oxidation of thiocyanate.The band at 450 cm−1, typically assigned to bridge‐bound SCN, corresponds to the gold‐SCN complex. Additionally to SCN− oxidation to cyanate, the dissolution of gold surface has been observed at high positive potentials.
ISSN:0377-0486
1097-4555
DOI:10.1002/jrs.4944