直接甲醇燃料電池非貴金屬陰極觸媒：鈷氮化合物之合成與應用

Preparation and application of Co-N electrocatalyst for DMFC

陳韻宇(Yun-yu Chen)

指導教授 ： 陳郁文

國立中央大學/工學院/材料科學與工程研究所/碩士(2008年)

摘要

直接甲醇燃料電池(DMFC)為目前最接近商業化的燃料電池之一，由於在低溫操作，必須使用電極觸媒催化燃料及氧化劑來提升效能。目前陰極觸媒以白金為主，但白金價格一直居高不下，使得燃料電池的推動面臨一大障礙。開發可取代白金之新型非貴金屬電極觸媒為加速燃料電池商業化的首要課題之ㄧ。
本研究從碳載體種類、載體改質方法和聚吡咯摻雜量等方面針對非貴金屬陰極觸媒Co/PPy/C進行研究與開發，透過碳載體的改質技術可大幅的提升碳材表面含氧官能基，提升合成觸媒時碳材表面與觸媒前驅體的作用；也使觸媒性質由疏水性轉為親水性，增加製作MEA時塗佈觸媒的均勻性。此外，也藉由改變聚吡咯摻雜量，提高活性中心(Co-N4)數量，使觸媒活性得到提昇。

關鍵字

直接甲醇燃料電池 ； 鈷 ； 氧還原 ； 聚吡咯 ； 電極觸媒

並列摘要

Direct methanol fuel cell has all the qualities to qualify itself as the major power supply of the future and is very close to commercial realization. As a result of low temperature operation, DMFC must use catalyst to catalyze the conversion of fuels and oxidant in order to accomplish the desired efficiency. The best electrocatalyst for both conversions are platinum. The high cost and availability of platinum has become a major obstacle to the realization of DMFC. In order to solve this problem, development of non-precious electrocatalyst for DMFC is highly desirable.
In this work, we investigate the possibility of using Co/PPy/C as the cathode electrocatalysts for DMFC. Major endeavors include types of carbon support, carbon modification and the content of polypyrrole. Carbon modification was employed in order to increase the oxygen functional group on carbon surface and to promote the interaction between support surface and catalyst precursor. Furthermore, it can also control the hydropbobicity to hydrophilicity of the catalyst. This control in surface properties is essential to obtain uniformly dispersed catalyst ink in the MEA fabricating process. In addition, we also increase the the content of polypyrrole in order to increase the amount of active center(Co-N4). It can raise the activity of the catalyst in oxygen reduction reaction.

並列關鍵字

DMFC ； eletrocatalyst ； cobalt ； polypyrrole ； ORR

參考文獻

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