Abstract:

Ag colloidal particles in a size range of about 80—90 nm were prepared by silver nitrate solution reduced with sodium citrate.  We collected the surfaceenhanced Raman spectra of 10^-13 mol/L aqueous R6G via 1 mW of laser power and 5 s of integration time. 10^-11 mol/L aqueous R6G was detected by airdried Agfilm method. When the density of Ag colloidal particles decreased, then the ability of surfaceenhanced Raman scattering decreased rapidly.

Key words: surfaceenhanced Raman scattering, R6G, ultratrace amount of molecules