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In recent years, in order to deal with the increasingly serious energy crisis and environmental pollution, the countries in the world attaches great importance to the development of new energy sources, fuel cell vehicle hydrogen fuel rapid development. However, the development of the commercialization of fuel cell vehicles is still constrained by the high cost, durability, subject to conditions improve and infrastructure. Touch for proton exchange fuel cell (PEMFC), one of the main research topics are known as universal in cost and durability of Pt, and thus the development of a high-performance, low-load, high stability The electro-catalyst to reduce the dependence of Pt, reducing the cost of fuel cells, has become the urgent need to solve the problem within the field of fuel cell research. In this thesis work focused on the Pt-CeO2 / C, the Pt-Ce0.8Zr0.2O2 / C and Au @ Pt / C catalyst preparation and characterization, and achieved the following progress: (1) using TEM, XRD, CV, LSV, CO -Stripping and examined in detail the different CeO2 content Pt-CeO2 / C catalyst morphology, dispersion, HOR activity, CO oxidation activity and single cell test. The results show that the performance of the Pt-20? O2 / C is optimal. CO oxidation on Pt-20? O2 / C starting at about 653 mV and 772 mV peak. Adding CeO2 for CO oxidation peak with commercial Pt / C catalyst compared to the negative shift of 60 mV homemade Pt-20? O2 / C catalyst CO tolerance performance was significantly better than the commercial Pt / C catalyst, and Pt-CeO2 / C catalysts on CO oxidation followed bifunctional mechanism. (2) using TEM, XRD, CV, LSV, CO-Stripping and other methods to examine in detail the different Ce0.8Zr0.2O2 content Pt-Ce0.8Zr0.2O2 / C catalyst morphology, dispersion, HOR activity, CO oxidation activity, and the test of a single battery. The results showed that-Pt-20? 0.8Zr0.2O2, / C optimal performance. CO oxidation on Pt-20? 0.8Zr0.2O2 / C starting at about 686 mV and 801 mV peak. The join Ce0.8Zr0.2O2 CO oxidation peak commercial Pt / C catalyst compared to a negative shift of 30 mV, homemade Pt-20? 0.8Zr0.2O2 / C catalyst CO tolerance performance is better than the commercial Pt / C catalyst, but worse than Pt-20? O2 / C catalyst. The colloid prepared core-shell structure (3) Au @ Pt / C catalyst. When with ascorbic acid as a reducing agent, PVA as a protective agent, the ORR activity of the the of Au _AT_ Pt / C catalyst is the best. After the elements ratio optimization available, the ratio of 2:4 by UV-Vis, XPS and TEM characterization of Pt completely coated Au when Au and Pt atoms that form a complete core-shell structure of Au @ Pt / C catalyst. ORR test results show that the Au @ Pt (2:4) / C catalyst, the initial reduction potential was 0.925 V, the half peak potential of 0.643 V, the limiting current density of 4.1 mA/cm2, the commercial Pt / C catalyst. After RDE test found that Au @ Pt (2:4) / C catalyst for the oxygen reduction catalyzed by 4e-mechanism to form water. Single cell test results show that, when the fuel cell cathode catalyst Au @ Pt (2:4) / C catalyst, the open circuit voltage of 1.0 V, the maximum power density is 479 mW/cm2.
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