The Effect of Halide Ions on SERS from Quinaldinic Acid Adsorbed on Colloidal Silver Surfaces

In this paper we discuss the effect of halide ions on the SERS spectrum irom quinaldinic acid adsorbed on colloidal silver surfaces, analyze origins of the effect and draw the following conclusions:The silver sol is remarkably aggregated by quinaldinic acid and the SERS effect is produced;Added into this aggregated sol system, halide ions can partially or completely replace the molecules of quinaldinic acid adsorbed on colloidal silver surfaces and to a different extent result in destruction of the aggregated sol system, and therefore the SERS signals of quinaldinic weaken largely and even vanish.