Synthesis and characterization of silver sulfide nanoparticles containing sol-gel derived HPC-silica film for ion-selective electrode application

Silver sulfide nanoparticles dispersed in sol-gel derived hydroxypropyl cellulose (HPC)-silica films have been successfully synthesized using H2S gas diffusion method. This is the first attempt to produce silver sulfide nanoparticles using this technique. Ag2S nanoparticles are generated through reaction of H2S gas with AgNO3 precursor dissolved in the HPC-silica matrix. Transmission electron microscope (TEM) and atomic force microscope (AFM) analysis reveal nanoparticles size distribution from 2.5 nm to 56 nm for H2S gas exposed sample. The surface chemistry of Ag2S nanoparticles and sol-gel derived HPC-silica matrix is confirmed by X-ray photoelectron spectroscopy (XPS). The negative shifts in the core-level XPS Ag (3d) binding energy of Ag2S nanoparticles are attributed to Ag : S surface atomic ratio exhibited by these nanoparticles with varying processing conditions. Following processing and characterization, suitability of the present method to produce silver sulfide ion-selective electrode is demonstrated by depositing Ag2S nanoparticles on a graphite rod. The high reponse function of the electrode is due to the presence of nanoparticles.