Article

Enhancements in intensity and thermal stability of Raman spectra based on roughened gold substrates modified by underpotential deposition of silver

General Education Center, Vanung University, 1, Van Nung Road, Shuei-Wei Li, Chung-Li City, Taiwan
Journal of Raman Spectroscopy (Impact Factor: 2.67). 08/2009; 40(8):903 - 907. DOI: 10.1002/jrs.2196

ABSTRACT

In this study, electrochemically roughened gold is modified with underpotential deposition (UPD) silver to investigate the effects on enhancements in the intensity and the thermal stability of surface-enhanced Raman scattering (SERS). The SERS of Rhodamine 6G (R6G) adsorbed on the UPD Ag-modified Au substrate exhibits a higher intensity by six-fold of magnitude, as compared with that of R6G adsorbedon the unmodified Au substrate. Moreover, the SERS enhancement capabilities of UPD Ag-modified Au and unmodified Au substrates are seriously depressed at temperatures higher than 200 and 150 °C, respectively. It indicates that the modification of UPD Ag can significantly depress the thermal destruction of SERS-active substrates. Copyright © 2009 John Wiley & Sons, Ltd.

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