奈米碳管改質聚乙烯醇複材特性研究與甲醇燃料電池的應用

The application of Poly (vinyl alcohol)/carbonnanotube composite in Methanol Fuel cell

陳文祥(Wen-Hsiang Chen)

指導教授 ： 陳兆勛

國立臺灣大學/工學院/高分子科學與工程學研究所/碩士(2012年)

https://doi.org/10.6342/NTU.2012.01694

摘要

燃料電池是現今替代能源的一個重要研究議題，因為它方便攜帶，燃料容易取得，而且不會排放破壞環境的廢棄物，是很有潛力的新一代能源，但是目前燃料電池成本昂貴，如何利用較低的成本，製造高效率的燃料電池，是許多研究的方向。

本實驗將奈米碳管用硫酸與硝酸進行磺酸化改質，使碳管壁上結合親水磺酸根，在超音波震盪可以均勻分散在水中。我們將奈米碳管溶於聚乙烯醇/聚磺酸化苯乙烯溶液中，依照不同成分加以編號，混和均勻後再溶液倒入塑膠培養皿中，烘乾成膜。之後利用戊二醛做交聯劑，在聚乙烯醇薄膜表面進行縮合交聯反應，交聯後的薄膜能在水中不被水解，最後薄膜浸泡鹽酸溶液以增加薄膜的質子含量。

我們進行聚乙烯醇複材的特性分析，包括離子傳導度，飽和含水率，甲醇滲透度、拉伸強度的測試，最後以本實驗室研發的燃料電池系統進行電池效能測試，實驗結果發現，添加聚磺酸化苯乙烯能有效增加薄膜的質子傳導度，較純PVA膜增加10倍，並且有效減低質子傳導的阻礙。添加奈米碳管後，薄膜機械強度較純PVA增加2.5倍，甲醇滲透率減低至7.07 × 10-10 cm2/s，較Nafion 117的1.86 × 10-6 cm2/s低許多，並使含水率提高。電池性能方面，添加奈米碳管有效使燃料使用率提高至99％，有效阻絕甲醇滲透到陰極而造成電流降低，而電池效率為18％。在成本、效能上都表現優異。

關鍵字

聚乙烯醇 ； 聚磺酸化苯乙烯 ； 奈米碳管 ； 甲醇燃料電池 ； 質子交換膜

並列摘要

The energy problems are serious topic this days. The fuel cell is a potential energy in the future, because people get the fuel-methanol easily, and the cell is light, easy to take, and we won’t make any pollution to the environment.

In this research, we used sulfuric acid and nitric acid to make the carbon nanotube sulfonated. The wall of tube are full of sulfonated bonds, and we solved the tube into water with ultra-sonic vibration. Than we solve the nanotube into PVA/PSSNa solution, and pull the solution into plastic dish. After drying , the solution change into membrane, we put the membrane in hydrochloric acid/glutaraldehyde/acetone solution, in order to make the polymer membrane cross-linked. Than we put the cross-linked membrane in hydrochloric acid.

The membrane was analysed , included water consist, ion conductivity, methanol permeation, tensile strength, and cell test. The membrane ion conductivity was improve with adding PSSNa, and decrease the resistance of ion conduction. The ultimate strength and water consist of membrane was improved with adding carbon nanotube and decrease the methanol permeation. In fuel cell testing, the fuel efficiency was increase to 99％ with adding carbon nanotube. The cell efficiency is 18%, with low cost.

並列關鍵字

poly (vinyl alcohol) ； PSSNa ； carbon nanotube ； DMFC

參考文獻

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