Study of Role of Silver Nanoparticles on Spectroscopic Properties of a KetocyanineDye

Abstract

The role of silver nanoparticles on spectroscopic properties of the ketocyaninedye 2,5-di[(E)-1-(4- dimethylaminophenyl) methylidine]-1-cyclopentanone (2,5-DMAPMC) has been investigated using absorption and fluorescence spectroscopy. Silver nanoparticles are synthesized by chemical reduction method and estimated size from SEM measurements is 22 nm. The changes in absorption spectrum of dye in the presence of silver nanoparticles suggest the possible interaction with silver nanoparticles. The Stern-Volmer plot of fluorescence quenching is found to be nonlinear showing positive deviation. The magnitude of quenching rate parameter and fluorescence lifetime measurements indicates the presence of both collisional and static quenching mechanisms. The binding constant and number of binding sites for static part of the quenching have been