本研究以改良直接甲醇燃料電池(DMFC)電極觸媒為主要的課題，而以降低貴重金屬的用量並提高電化學活性為目標。觸媒是以碳黑(CB)與中孔碳(MC)為基材，在其上生長碳奈米管製成海膽狀碳材，再以它為擔体，製備含10 wt%Pt的Pt1Ru0.75Sn0.5/C觸媒並製成觸媒電極，探討碳基材種類、硝酸鐵含浸濃度、碳奈米管生長溫度及時間等因素，對碳基材上碳奈米管生長情形及製成觸媒電極後用於甲醇氧化的電催化活性的影響。此外也採取多次含浸法製備觸媒，藉以進一步提昇其效能。
結果顯示：碳粒上有碳奈米管的生成，形成海膽狀碳材；以其為擔体製備的Pt1Ru0.75Sn0.5觸媒，都比以純粹碳粒為擔体製備者，有較高的電催化活性，碳奈米管不但可以改進碳材導電度，也當作連接碳粒間的橋樑，因此可以增進燃料電池的效能。
對碳黑而言，在改變不同變因下，得到海膽狀碳黑(ULCB)最佳參數為以溼式含浸法含浸10000 ppm硝酸鐵溶液一次，在800 oC下，通入1 %乙炔持溫30分鐘。至於用於電催化甲醇氧化反應的觸媒則以臨濕含浸法含浸三次總量為10 % Pt於用鹽酸去鐵後的海膽狀碳黑上所製備的PtRuSn/Fe-free ULCB觸媒活性最佳，其效能比商用E-TEK (20 % PtRu)觸媒高出三到四成，可與Johnson-Matthey(20 % Pt、10% Ru)觸媒匹敵。

The main objective of this study is to improve the performance of the anode catalyst in direct methanol fuel cell and to cut down the using amount of valuable metal. Carbon black (CB) and mesoporous carbon (MC) were employed as the substrates to prepare two kinds of urchin-like carbons with acetylene as the carbon source and iron as the catalyst. The influence of preparation methods and conditions, including the kind of substrates, impregnation concentration of Fe(NO3)3, temperature and time of carbon nanotube growth etc, on density and growth rate of the carbon nanotubes (CNTs) will de explored. The urchin-like carbons, as the supports, were then loaded with Pt (10 wt %), Ru and Sn to prepare PtRuSn/ULCB and PtRuSn/ULMC electrocatalysts, for methanol oxidation. The effects of using multiple impregnation in the preparation of urchin-like carbons and electrocatalysts on the performance of catalyst were also investigated.
Experimental result reveal that carbon nanotubes grow on the carbon particles and forming urchin-like carbon (ULCB and ULMC), and the electrocatalytic activities of the catalysts with these urchin-like carbons as the supports for the electrooxidation of methanol are higher than those with CB and MC as the supports. CNTs in the urchin-like carbons play the role of connecting the carbon particles and can enhance the performance of the electrode in DMFC because of their high electrical conductivity.
The best conditions for depositing carbon nanotubes on carbon black is impregnating carbon black with 10000 ppm Fe(NO3)3 solution once , followed by feeding with 1 % acetylene and heating up to 800 oC for 30 minutes. Electrocatalyst (containing 10 % Pt,4 % Ru and 3 % Sn) prepared by multiple impregnation with the electrocatalytic metals (Pt, Ru and Sn) on the Fe-free ULCB exhibits the highest performance, even has a higher electrocatalystic activity for methanol oxidation than the commercial E-TEK (20 wt% Pt and Ru) and Johnson Matthey(20 % Pt、10 % Ru) catalysts.

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