目前應用於直接甲醇燃料電池最有效的觸媒為鉑觸媒，包括陽極與陰極，主要原因是鉑對陽極甲醇的催化氧化及陰極氧分子還原反應，顯示出較高的活性，且鉑在酸性介質中有較高的穩定性及耐腐蝕性。然而鉑金屬價格昂貴，且使用鉑金屬當陰極觸媒會有兩大問題，甲醇從陽極滲透到陰極造成混合電位及鉑金屬活性中心被毒化，所以對於陰極觸媒，尋求對氧分子還原反應有高活性且廉價的非鉑金屬觸媒是讓直接甲醇燃料電池能商業化的重點之一。
本研究使用碳化鎢作為直接甲醇燃料電池之陰極觸媒的載體以及使用鈀與鈷兩金屬來形成二元合金觸媒代替鉑金屬當作直接甲醇燃料電池陰極觸媒，探討以不同煅燒溫度和製備方法所合成的碳化鎢、不同觸媒前驅物、觸媒合成方法及還原溫度對氧分子還原反應（ORR）活性及抗甲醇毒化之影響。利用旋轉圓盤電極和循環伏安法來判斷觸媒的活性。
結果顯示，PdCo/WC在1M甲醇0.7V與0.8V環境下的抗甲醇毒化能力比PdCoW/C觸媒好，證實了使用碳化鎢當陰極觸媒載體所合成出來的觸媒比使用碳黑當載體所製備的陰極觸媒之活性還要高，且碳化鎢對觸媒的抗甲醇毒化能力有提升的效果。所有PdCo/WC系列觸媒在有甲醇0.7V與0.8V環境下皆具有抗甲醇毒化的能力，在0M甲醇濃度0.7V環境下的活性也比商用觸媒JM13100好。因此使用鈀鈷金屬所得的觸媒不僅具有抗甲醇毒化的能力，且使用鈀金屬取代鉑金屬，可將成本大幅降低。此外，使用偏鎢酸銨當鎢前驅物經過900℃煅燒溫度合成的碳化鎢載體，具有較高氧分子還原反應的活性。另外，使用化學沉澱法製備的鈀鈷觸媒活性皆優於使用含浸法製備的鈀鈷觸媒。

Platinum is the most effective electrocatalysts for use in Direct Methanol Fuel Cell (DMFC),both anode and cathode, because of it’s high catalytic activity for methanol oxidation in anode and oxygen reduction reactions (ORR) in cathode. Platinum also has very high stability and good corrosion resistant under acidic operating medium. However, platinum is too expensive for use in DMFC and another problem in using platinum at the cathode is the methanol crossover problem. Methanol crossover to the cathode created both over-potential and active site poisoning problems when Pt is used. The search for more active and less expensive non-platinum based catalysts for oxygen reduction reaction (ORR) is one of the most important issues towards the commercialization of DMFC.
This thesis explores using the tungsten carbide as carries of DMFC cathode catalyst, and the possibility of using palladium and cobalt form a binary catalyst, instead of platinum catalyst, as the basic component of the DMFC cathode catalyst. The effect of preparation method for tungsten carbide and cathode catalysts, different precursor, temperature of reduction and catalyst formulations towards ORR activity and methanol tolerance were explored in this thesis. Catalyst performance were studied using Rotating Disk Electrode (RDE) and Cyclic Voltammetry (CV).
Results in this study revealed that all PdCo/WCχ catalysts in 1M methanol 0.7V and 0.8V have better ability of anti-poision than PdCoW/C catalysts in the presence of methanol. It’s been proven that the catalysts synthetized by tungsten carbide as cathode carries have higher activities than carbon black as cathode carries. Moreover, tungsten carbide has positive effect to catalysts on the abilities of anti-poision in methanol. All catalysts of PdCo/WC series has the abilities of anti-methanol poision in 0.7and 0.8V methanol. In the 0.7V environment of 0M methanol, the activity is also better than commercial catalysts JM13100. Therefore, the catalyst acquired by using Palladium and Cobalt not only has abilities of anti-methanol poision but also cost down by using Palladium to replace Platinum. Tungsten carbide prepared with (NH4)6W12O39•xH2O and 900℃ for temperature of calcination as the WC precursor have highest activity. Besides, catalysts prepared using precipitation as method have higher activity than impregnation.

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