在直接甲醇燃料電池中，價格昂貴以及鉑觸媒被甲醇毒化造成燃料電池效能降低的問題一直難以得到解決，導致無法商業化。而近幾年有許多研究皆為使用過渡金屬環大錯合物做為陰極以改善甲醇毒化的問題，且價格低廉，如CoTMPP/C，但氧還原能力卻無法有明顯的提升。
本研究為使用Vitamin B12與活性碳混合後進行熱燒結，製成B12/C之觸媒。Vitamin B12之中心結構也為過渡金屬環大錯合物，中心金屬為鈷，但中心環狀結構為corrin，不同於先前研究中之金屬環大錯合物結構。
本研究比較具有不同官能基之Vitamin B12，進行電化學氧還原半反應測試，得知不同官能基之B12/C皆具有相似的氧還原能力，並使用XAS等儀器進行結構分析推測燒結後皆為同樣之結構。並推測由於燒結後將不必要之官能基移除，使cobalt corrin形成一非平整之平面結構而利於與氧氣反應。
從電化學測試中明顯發現B12/C之觸媒有優於CoTMPP/C許多的氧還原能力，且從測試中證實其不會被甲醇毒化，是極適合使用在DMFC之陰極觸媒，具有很大的潛力。

DMFC is a power-generating device, which coverts methanol and air/oxygen from chemical energy into electrical energy. However, the high-loading Pt utilization and the methanol crossover are thought to be the major issues to hinder the DMFC commercialization. In recent years, N4-metal macrocycles as cathode catalysts, which are not only insensitive to methanol but also low cost, are studied. However, these N4-metal macrocycles still have low oxygen-reducing activity compared to Pt catalysts.
Vitamin B12 is a cobalt-containing corrin ring structure. There are four kinds of vitamin B12 compounds, due to various radicals bonding with cobalt, and they are B12(-CN), B12(-CH3), B12(-OH) and B12(-Ado). In this study, various B12 compounds were mixed with activated carbon, and then the mixture was pyrolyzed by thermal chemical vapor deposition at various temperatures in N2-atomsphere, forming B12/C. It indicates that all kinds of B12 compounds have the similar electrochemical performances and structures after the pyrolysis. Which the central corrin ring structures were changed from octahedral structure to distorted square plane. Besides, the radicals bonding with cobalt were also removed. From electrochemical analysis, B12/C catalysts have better ORR ability than CoTMPP/C, and they perform the same ORR activity even in a methanol-containing solution. By DMFC tests, a single cell using B12/C catalysts in the cathode, which shows 40, 34 31, 29 and 29 mW cm-2 by feeding 1, 2 ,4 ,6 and 8 M methanol to the anode, respectively, indicating that B12/C catalysts have high ORR activity with methanol tolerance.

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