奈米碳管合成及接枝應用於直接甲醇燃料電池膜電極組之研究

Study on the Synthesis and Grafting of CNTs and CNTs-assisted MEA for DMFC Applications

洪新欽(Hsin-Chin Hung)

指導教授 ： 林啟瑞 ； 蘇春熺

國立臺北科技大學/機電學院/機電科技研究所/博士(2007年)

摘要

本研究的目的在於新穎奈米碳管的合成方法及接枝奈米碳管技術應用於直接甲醇燃料電池之膜電極組上。考量基材尺寸侷限效應及微波電漿效應影響奈米碳管合成的情形下，進行一連串的實驗分析，實驗結果發現基材的尺寸侷限效應對於接枝碳管的成長有很大的影響，本研究藉由大量實驗數據建立估算接枝奈米碳管直徑的數學估算模型，經由更進一步的實驗結果合成出2 nm之奈米碳管，此結果和利用數學估算模型推算出來的趨勢有相當程度的吻合。本研究開發出一套自呼吸空氣式直接甲醇燃料電池的製程，並應用接枝奈米碳管於直接甲醇燃料電池的膜電極組，實驗結果顯示當使用自製接枝奈米碳管觸媒載體的陰極搭配E-Tek公司的陽極時有最低的電位降趨勢及最高的開路電壓0.6 V，當在0.25 V的負載之下，可得尖峰功率0.009 W。此外，本研究利用紫外光輔助直接甲醇燃料電池發電，結果顯示使用3 wt%的甲醇8 ㏄，在照射紫外光的情形下，由原本總輸出能量101.6 mW×hr提升至226.16 mW×hr。本研究結果將很有希望應用於燃料電池產業，突破現有技術瓶頸。

關鍵字

微波電漿化學氣相沈積 ； 奈米碳管接枝法 ； 奈米碳管 ； 膜電極組 ； 直接甲醇燃料電池 ； 微波電漿

並列摘要

This research aims to study the synthesis of carbon nano-tubes (CNTs) and the fabrication of CNTs-assisted membrane electrode assembly (MEA) for direct methanol fuel cell (DMFC) applications. At first, CNTs were grown using the grafting method. The grafted CNTs were analyzed on effects of size-confinement and microwave plasma. The size-confinement effect was observed to have significant effects on grafted CNTs growth. The mathematical model for estimating the diameter of the grafted CNTs was verified experimentally, results show that grafted CNTs with diameter of 2 nm is well coincide with the mathematical model. A process is developed to fabricate the air-breathing type DMFC. A novel grafting method to fabricate the CNTs-assisted MEA of DMFC is presented. Results show that MEA fabricated with grafted CNTs for cathode and E-Tek catalyst electrode for anode have the smallest potential drop and highest open circuit votage (0.6 V), and the peak power can be increased up to 0.009 watts at 0.25 V. Besides, the UV enhanced DMFC have been carried out in this research. Results showed that at the constant cell voltage 0.4 V, the total output energy of 3 wt% 8 ㏄ methanol can vary from 101.6 mW×hr to 226.16 mW×hr by UV light irradiation. From this study, it showed that the techniques is probable using in the fuel cell industry.

並列關鍵字

MPCVD ； CNTs grafting method ； CNTs-assisted MEA ； DMFC ； CNTs ； fuel cell ； Microwave plasma

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