GOLD AND PLATINUM MONO AND BIMETALLIC NANOPARTICLES AS TOXIC METALS SENSOR IN AQUEOUS MEDIA

摘要

Mono metallic gold, platinum and bimetallic platinum core gold shell (Pt-Au) with 1:1 mole stoichiometric, nanoparticles is synthesized in chemical method with Cetyltrimethylammonium bromide (CTAB) as the capping agent. The particle sizes are characterized by UV-Vis, HRTEM, HRSEM and XRD measurements respectively. The nanoparticles are tested on the novel chemical sensor for the spectrophotometry detection of toxic metals like Hg2+, Pb2+, Cr3+, Se4+, Ti4"1", and Co2+ salts is described. The sensor is based on a surfactant stabilised metal nanoparticles in an aqueous solutions of Pb2+, Cr +s Se4+; Ti4+, Hg2+ and Co2+ results in a rapid spectrophotometry response, with both a high selectivity and a sub-micromolar sensitivity. The effects of pH, nature of mono and bimetallic catalysts are studied and the reaction conditions are optimized. Bimetallic nanoparticles exhibited better sensing properties than the mono metallic nanoparticles, which may be due to the electronic effects of the core to shell metal atoms.