The Study Of Tungsten-Based Supporters For Pemfc Catalyst

Proton Exchange Membrane Fuel Cell(PEMFC) is highly efficient, safe and green, so it is paid much attention. Through the efforts of many researchers, the research and development of PEMFC have been made great progress. However, there are still some problems for practical applications for PEMFC, such as catalyst activity and cycle life.This paper studied tungsten carbide and tungsten oxide as the supporter for the catalyst in order to solve these problems.Tungsten carbide and tungsten oxide materials are relatively stable in application for fuel cell. There is synergistic effect with the metal catalyst, so that they are ideal alternatives to the carbon. Currently, the main problem of these substances is that the specific surface area is too small which leads to metal catalysts disperse uniformly. High surface area mesoporous supporters were made from SBA-15, source and AMT by temperature-programmed mehtod.This thesis compared the purity of tungsten carbide made at presence of CO with the presence of H2. It was found that high concentration of CO atmosphere was more conducive. It was proved that the tungsten carbide was nanochain-structured mesoporous. The Pt-WxC/C(C/W=10, BET=558m²/g) catalysts synthesized by continuous microwave irradiation technique were more active than Pt/C (e.g. formic acid oxidation, oxygen reduction and resistance to CO poisoning).Further more, increasing the content of tungsten carbide would be useful for catalysis. Catalyst made by intermittent microwave irradiation method was more active for formic acid oxidation than that made by continuous microwave irradiation method.This paper synthesized W18O49, which is a hypoxia crystal of WO₃, with CTAB. Pt on this supporter was very active for hydrogen adorption and desorption, but it not performed as well as Pt/C for its smaller particle size.In this paper, the BET of WO₂/C using SBA-15 as a template was reaching 1191m² /g. Formic acid oxidized through dehydrogenation-based path with the presence of WO₂. It was found that catalysts performed not as good as expected due to carbon with low graphitization on the supporters. The tungsten-based catalysts prepared were highly active and high resistance to CO poisoning. The tungsten-based catalysts with little amorphous carbon would be very useful for PEMFC.