The Preparation And Application Of Precious Nanoparticles In Reverse Microemulsion

Nanomaterials have become a hot sopt of today’s scientific research due to thespecial properties which are different from conventional materials and singlemolecules. Electrochemical preparation of nanoparticles has the advantages of simpleequipment, easy to operate, mild reaction conditions and easy to control.Microemulsion is a thermodynamically stable dispersion, isotropic, transparent ortranslucent system which consists of oil, water and surfactant, usually the water in oilmicroemulsion is called the reverse microemulsion. The octyl polyethylene glycolphenyl ether(TX-100) reverse microemulsion containing large amounts of hydrogenions has good conductive property and can be used as soft template forelectrochemical studies.In this dissertation TX-100reverse microemulsion was used as medium,nanometer Au assembly membrane and Pd Au bimetallic nanoparticles were preparedby electrochemical method. The morphology, nano-structure and propertiesapplication of the nanometer Au assembly membrane and Pd Au bimetallicnanoparticles were searched by electron microscopy(SEM), cyclic voltammetry (CV)and time current analysis. The main research work is as follows:(1) Using the reverse microemulsion prepared with octyl polyethylene glycolphenyl ether(TX-100)、n-hexane, n-hexanol and chlorine acid as soft template, the“nano-pool” dissolves in reverse microemulsion was self-assembled on the ITOelectrode surface by electrochemical self-assembly. The morphology and catalyticactivity of the nanometer Au assembly membrane were searched by scanning electronmicroscopy and cyclic voltammetry methods to investigate. The assembly membraneprepared in water solution was also researched for comparison. The results showedthat the Au nanoparticles in assembly membrane prepared in the TX-100reversemicroemulsion distributed more uniform and exhibited better catalytic activity andelectrochemical stability. The current density and basement also affect on themorphology and catalytic activity of the assembly membrane.(2) Based on the good electrical conductivity of TX-100reverse microemulsioncontaining large amounts of hydrogen ions, the Pd-Au bimetallic nanoparticles wereprepared by electrodeposition. The morphology and catalytic activity of the bimetallicnanoparticles were investigated by scanning electron microscopy and cyclicvoltammetry methods, and compared with the bimetallic nanoparticles prepared in mixed surfactants and CTAB reverse microemulsion. The results showed that thedifferent depositional system can influence the formation and catalytic activity ofPd-Au bimetallic nano-particles. The Pd-Au bimetallic nano-particles prepared inTX-100reverse micoroeulsion have the best catalytic activity, anti-poisoning andelectrochemical stability.