| A Pt/C (20w%) electrocatalyst was prepared by a modified polyol synthesis strategy (EG method). XRD, TEM and electrochemical characterization (CV) show that high and homogeneous Pt particles deposite on carbon support, with a mean particle size of 2.4 nm. Enhanced ORR activity and superior performance were obtained when it was employed as cathode catalyst in DMFC test. Effects of various conditions for preparation of Pt/C on DMFC performance were researched.Pt-Fe/C catalysts with different Pt-Fe ratio were prepared by EG method and the optimal ratio of Pt-Fe was determined. The optimal Pt-Fe/C catalyst shows an enhanced ORR activity than that of Pt/C in RDE and DMFC tests, which may be attributed to its larger Pt electrical surface area and more Pt-Fe alloy form. Pt-Fe/C300 catalyst with larger surface area was also obtained under reduction at a moderated temperature (300癈), the increase in ORR for the Pt-Fe/C300 could be explained by the enhancement of H2O2 decomposition rate on Pt/C in presence of Fe3+. A synthesis mechanism for preparation of Pt-Fe/C catalyst by using EG method was proposed by the combination of XRD, TEM, chemisorptions results.Highly dispersed Pt/MWNTs was prepared by EG method and a possible synthesis mechanism was proposed. Pt/MWNTs was firstly used in DMFC as cathode catalyst and it showed better ORR activity and superior cell performance than Pt/XC-72, which may be attributed to its unique electric characteristic, tubular structure and low sulfur content. It was also found that the mean particle size and particle size distribution of Pt in Pt/MWNTs could be controlled by simply adjusting DI water content in the preparation system. Thus the Pt/MWNTs with the highest ORR activity was obtained.CV, RDE and DMFC tests show that Pt-Pb/C does not possess expected methanol tolerant capability.
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