Surface plasmon assisted Raman scattering from electrochemically controlled adsorbates on flat, single crystal silver

✍ Scribed by S.P. Byahut; T.E. Furtak

• Publisher: Elsevier Science
• Year: 1991
• Tongue: English
• Weight: 414 KB
• Volume: 36
• Category: Article
• ISSN: 0013-4686
• DOI: 10.1016/0013-4686(91)85061-b

✦ Synopsis

Ahstraet-We have operated a device which exploits surface plasmon field enhancement through the Kretchmann configuration to improve the surface sensitivity of the Raman process. The sample was Ag(ll1) grown epitaxially on mica. We collected the entire emission cone to real& the full coupling efficiency. With 2 mW of incident radiation at 514.5 nm we obtained a signal-to-noise ratio in excess of 400 with a 600 channel integration time of 400 s in Raman scattering from para-nitrosodimethylaniline at monolayer coverage. When come&d to an electrochemical cell, this method enabled us to systematically study mild roughening and the eventual change in surface chemistry. We have shown that even with 2 ML of surface restructuring the adsorption sites for the pNDMA are noticeably more acidic. These sites produce the dominant scattering under normal surface enhanced Raman conditions on randomly rough electrodes.