Study Of The Preparation Of One-Dimensional Inorganic Nanomaterials And Their Electrochemical Performance

Direct Methanol Fuel Cell (DMFC) has attracted more and more attention from researchers because of high ener gy density, simple equipment, environmentally friendly and many other advantages, and these make it have potential applications in renewable energy. Pt-based catalysts have been considered to be the best catalysts for oxidation of methanol, however, Pt-based anode materials used usually have low reaction kinetics, easy poisoning and fuel permeation and so on. To solve the above problems, this dissertation focused on the preparation of the metal oxide TiO2 nanofibers and its application in support material of DMFC anode catalyst, which could further improve the electro-catalytic properties for methanol and promote large-scale commercial application of DMFC. The research contents are as follows:1. TiO2 nanofibers were synthesized by electrospinning technology and high-temperature calcination. And Xwt% Pt/TiO2 electrocatalysts were prepared by impregnation reduction method with different Pt nanoparticles. The composition, the morphology and microstructure of various catalysts are characterized by SEM、TEM、EDS and XRD, etc. At the same time, the electrooxidation of methanol was tested by cyclic voltammetry and chronoamperometry using a three-electrode system in an acidic solution for the samples. The results show that 21wt% Pt/TiO2 nanofiber catalyst has excellent catalytic activity and stability of methanol oxidation, but the anti-poisoning ability is weaker than 10wt% Pt/TiO2 nanofiber catalyst.2. To study the effect of different catalytic supports on methanol oxidation. The Pt/P25 was prepared with the same mass fraction of Pt nanoparticles by the same experiment. The microstructure and the electrocatalytic activities towards the methanol of Pt/TiO2 and Pt/P25 catalyst were measured, which were compared with commercial Pt/C catalyst containing the same quality percentage of Pt nanoparticles. The results reveal that the Pt/TiO2 nanofiber catalyst exhibits highest catalytic activity and stability towards the methanol electooxidation, but Pt/P25 has the best anti-poisoning performance.3. Graphene oxide(GO) was prepared by the modified Hummers, and a novel TiO2-GO nanofiberous structure with different amounts of GO was synthesized by electrospinning and then calcinated in N2 atmosphere at 600℃. A series of Pt/TiO2-RGO(X) electric catalysts which contain about 10wt% Pt were obtained. Subsequently, the microstructure of the catalysts was characterized and the conventional electrochemical experiment of methanol electrooxidation was examinated. The results show that the Pt/TiO2-RGO(0.03) catalyst has the best methanol electrocatalytic properties, but the ability of anti-middle poison weaker than Pt/TiO2 nanofiber catalyst.