UV–Irradiation Induced Synthesis of Fluorescent Poly (Acrylic Acid) Stabilized Silver Clusters

Photochemical treatment using ultraviolet radiation was used to prepare fluorescent silver nanoparticles/nanoclusters from AgNO3 precursor upon its encapsulation with Poly (Acrylic Acid). Spectrofluorometric analysis showed an excitation spectra with maxima at approximately 450 nm and 550 regions nm when fixed wavelength of 600 nm was used to scan the solutions. Fluorescent emission occurred at around 500 nm and 700 nm using the 450 nm excitation wavelength. High molecular weight polymer (AgPAA1250) showed higher intensity of emission than low molecular weight (AgPAA450). Stability of the nanoparticle solution was assessed using Zeta Potential Measurements. Despite having a larger average particle diameter, Zeta Potential value for AgPAA 1250 is more negative than AgPAA 450, -59.3 mV and -47.5 mV respectively. This tells us that using a polymer with larger molecular weight can better prevent the aggregation of the nanoparticles