Characterization and Synthesis of Silica-Coated Silver Nanoparticles by Sol-Gel Method with Controlling of Adding Ammonical Silver Nitrate Amount

Abstract

In this study, silica-coated silver nanoparticles (SSNPs) with a core-shell structure are successfully fabricated using a simple sol-gel method without using primer, surfactant or surface modification of core. To investigate the influence of ammonical silver nitrate (AgNO 3 ) on the synthesis of SSNPs, the amount of an aqueous solution of AgNO 3 was varied in the range from 3 to 12 mL. It was found that the thickness of silver shell could be formed in the range of ∼20 to ∼60 nm, and the UV-vis optical absorption measurement revealed a pronounced red-shift of the surface plasmon resonance (SPR) band from 442 to 516 nm.