One pot synthesis of silver nanoparticles on ITO surfaces: investigation of optical and electrochemical properties

Abstract

Dense layer of silver nanoparticles (AgNPs) was successfully prepared on indium tin oxide (ITO) surfaces by using a refined seed-mediated growth approach (RSMG). Prepared AgNPs/ITO film was investigated using several methods such as UV–vis spectroscopy, field emission scanning electron microscope, optical absorption, electrochemical impedance spectroscopy and cyclic voltammeter. The size and density of AgNPs on ITO surface were investigated and their governing parameters were discussed. The obtained results by using refined seed-mediated growth approach showed a narrower size distribution and a higher density of prepared AgNPs compared to those prepared by the normal seed-mediated growth method. The size of AgNPs was controlled by adjusting the growth time until 2 h, while if it is higher than 3 h, larger AgNPs with anisotropic shape were formed. Cysteamine molecules were used to ensure the attachment of AgNPs on the ITO surface and it was found to be effective for preparing dense and dispersed Ag NPs on ITO surface. The optical properties of prepared AgNPs layer with different density on the ITO surface were studied and discussed, using the full Mie theory for scattering and absorption by a homogeneous Ag sphere with modified dielectric constants.