Preparation and surface enhanced raman spectroscopic studies on Au-Ag alloy nanoparticles

Using citrate as protector, Au-Ag alloy nanoparticles with different molar ratios were prepared by using hydrazine as the reducer, One plasmon band between that of monometallic Ag and Au observed in their UV-Vis spectra indicated the formation of Au-Ag alloy nanoparticles. TEM results showed diameters about 25 nm and homogeneous color of the alloy nanoparticles without clear core-shell contrast. By using Pyridine as the probe molecules, SERS studies were performed. The results indicated the spectra of Pyridine adsorbed on alloy is different from that of Ag and Au.