Tuning of LSPR of Gold-Silver alloy nanoparticles with their composition

In the present study silver, gold and their alloy (Au1-xAgx (x = mole fraction of gold)) nanoparticles have been prepared under microwave irradiations. The prepared nanoparticles have been characterized using UV-Vis spectroscopy and high resolution transmission electron microscopy (HRTEM). The observance of single Surface Plasmon resonance (SPR) peak in the absorption spectra of Au1-xAgx alloy solutions attributed to the homogeneous formation of bimetallic alloy nanoparticles. There is linear red shift in observed SPR peak with increase in mole fraction (x). TEM images reveal the spherical shape of prepared Au1-xAgx alloy nanoparticles with average size ranging from similar to 4 - 17nm. The observed SPR peak have also been simulated using Mie Theory and DDA method.