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: 2.68). 02/2009; 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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