Study On Amphoteric Molecular Assisted Synthesis Of Ultra - Stable Platinum Nanoparticles And Their Electrochemical Properties

Precious metals (gold, silver and platinum, etc.) nanocrystalline materials haveunique electrical, optical, magnetic and catalytic properties，and these properties canbe controlled by their size, shape, structure and composition. They have greatpotential value in catalysis, sensors, medical diagnosis and treatment, and imaging. Inrecent years, tremendous progresses have been made on precious metals nanocrystals.Especially, the ifeld of nanostructure platinum catalysts showing excellentelectro-catalytic performance occupies a very important position. They have become ahot topic for numerous researchers. This paper focuses on preparation ofnano-platinum catalyst, as well as study the structure and electro-catalytic propertiesfor exploring their potential applications in catalysis electric field. The details of thisarticle are as follows:The ifrst job，Pt nanoparticles with an average size of2?3nm in diameter werereproducibly synthesized by reduction of t^PtCU solution containing Inositolhexaphosphate (IP6) as the stabilizing agent. The electron diffraction pattenr of thecubic nanoparticles revealed that they were single crystals with Pt (111) faces on thesurface. The Pt nanoparticles were used to modify electrode as a nonenzymatic sensor,the PtNPs-IP6modified electrode exhibited fast response and high sensitivity for H2O2detection. A low detection limit of2.0><10"7M (S/N=3) with wide linear rangesb3e"t7ween2.4x10"to1.3><10M (R2=0.9987) and between13x103to1.3x|0"2M(R"=0.9980) was achieved. The attractively electrochemical performances ofPtNPs-IP6made it as the promising material for the development of Pt-basedanalytical systems and other platform applications.The second work, the silver nanoparticles protected phytate with ultra-stableperformance synthesize IPyPt-Ag nano-particles which have hollow structure. Theresults of experimentals demonstrate that Ip6-platinum-silver nanoparticles form alloystructure rather than bimetal. IP6-Pt-Ag nanoparticles not only have uniform patriclesize but also good stability. In ifve kind of obtained catalysts, The samples ofIP6-Pt-Ag nanoparticles A4and A5exhibit good catalytic performance for oxidating methanol, All samples of IP6-Pt-Ag nanoparticles exhibit good catalytic oxidation andcatalytic reduction performance for hydrogen peroxide. The good catalyticperformances for methanol and hydrogen peroxide show that the catalysts can have agood prospect in fuel cells and electrochemical sensors.The third work，phytic acid dispersed carbon nanotubes dispersing in a glassycarbon electrode surface through self-loading act as the base materials. Atfer itspotentiostatic electrochemical deposition of platinum, catalytic performance formethanol has been explored. The structures of platinum are flower clusters withparticle size about800nm, DMF dispersed carbon nanotubes as the base materialsdeposited on the same particles, but the platinum flower clusters have significantlyagglomeration. The catalytic performance of Pt/PA-CNTs/GCE was significantlyhigher than Pt/GCE and Pt/DMF-CNTs/GCE for methanol oxidation. At ifrst, theantitoxic capability of Pt/PA-CNTs/GCE is not better than Pt/GCE andPt/DMF-CNTs/GCE. Atfer the stability experiments, the antitoxic capability ofPt/PA-CNTs/GCE is better than Pt/GCE and Pt/DMF-CNTs/GCE. And stableperformance of Pt/PA-CNTs is significantly better than the other two materials.