Surface-enhanced resonance Raman scattering (SERRS) spectroscopy has been applied to the analysis of chemically modified surfaces. The compounds 2,4,6-trinltrobenzenesulfonlc acid (TNBS), [Ru(bpy)2(Z-nlc)2pF,]2 (bpy = 2,2'- bipyrldyl, Z-nlc = Isonlcotlnic acid), and 2-[(4-hydroxyphenyl) azo]benzolc acid (HABA) were covalently bonded to a SnO2 surface through an amlnesllane linking group. Strong SERRS spectra of the covalently bound compounds were obtained following Ag deposition (by vacuum or chemical procedures) onto the derlvatized SnO2 surfaces. The optimal thickness of the overlayered Ag film for maximal SERRS effect was determined to be about 50 Å. Under these conditions, it was possible to detect submonolayer (<10% In the case of ruthenium complex) amounts of the chemically bonded species. In the case of HABA derlvatized SnO2 It was demonstrated that SERRS can provide structural Information about the covalently attached species. The technique was also successfully utilized to monitor changes In the SERRS spectrum during In situ electrochemical reduction of the NO2 group In TNBS which was covalently attached to the SnO2 surface. The advantages and disadvantages of the SERRS technique as applied to the analysis of chemically modified surfaces are discussed.
ASJC Scopus subject areas
- Analytical Chemistry