CHARACTERIZATION OF SILVER NANOPARTICLES SYNTHESIZED BY DIFFERENT CHEMICAL REDUCTION METHODS

Abstract

Silver nanoparticles (SNPs) were synthesized and characterized using different chemical reduction methods. Silver nitrate was used as precursor, and reduced to colloidal SNPs using different reducing agents such as tri-sodium citrate, hydrazine hydrate and sodium borohydride. The concentration of reductant was optimized to achieve colloidal SNPs in narrow size distribution followed by characterization with UV-visible spectrophotometer, Particle Size Analyzer (PSA), Scanning Electron Microscope (SEM) and Fourier Transform Infrared Spectroscopy (FTIR). The UV-Vis spectroscopy evident formation of SNPs having typical absorption maxima (λ_max) of 418 ± 2 nm. Particle size distribution (PSD) of the nanoparticles was obtained in the range of 60-80 nm, while SEM micrographs revealed the average size range of 100-200 nm. The FTIR spectra was found in the frequency range of 1380-1390 cm^-1 , indicating the stretch of nitro compounds as that obtained for silver nitrate which was used as precursor. Out of three reductants, tri-sodium citrate was found to be best as it provides narrow range of nanoparticles with higher stability compared with hydrazine hydrate and sodium borohydride.