矽氧化物及磷酸鋯改質PTFE/Nafion高溫質子交換膜燃料電池

Prepartion and characteristic of PTFE/Nafion High temperature proton exchange membrane modified by Tetraethoxysilane and Zr(HPO4)2 for fuel cell

葉信賢(Sin-Hsien Yeh)

指導教授 ： 林秀麗

元智大學/工程學院/化學工程與材料科學學系/碩士(2007年)

摘要

本研究是將PTFE/Nafion複合膜中加入tetraethoxysilane (TEOS)和磷酸鋯Zr(HPO4)2等無機粒子進行改質，以製備PTFE/Nafion-SiO2及PTFE/Nafion-Zr(HPO4)2種複合膜，並進行SEM、EDX、導電度及單電池等性能測試。膜材的導電度與相對濕度及溫度有關， 110~130℃下PTFE/Nafion-Zr(HPO4)2及PTFE/Nafion-Zr(HPO4)2複合膜的導電度介於1.47 ×10-3 ~ 1.75 ×10-3 S/cm，而Nafion212及PTFE/Nafion膜材的導電度介於1.32 ×10-4~ 1.50 ×10-4 S/cm。所製備的複合膜於相對濕度28.8 %~51.7％、溫度110~130℃及氫氣、氧氣皆為300 ml/min條件下進行單電池性能測試，PTFE/Nafion-Zr(HPO4)2複合膜最大功率密度可達600 mA/cm2 ~ 1200 mA/cm2， PTFE/Nafion-SiO2可以達到600 mA/cm2 ~ 800 mA/cm2，而同樣條件下Nafion 212膜材為300 mA/cm2 ~ 600 mA/cm2。由實驗結果顯示PTFE/Nafion複合膜中加入tetraethoxysilane (TEOS)和磷酸鋯Zr(HPO4)2等無機粒子進行改質可提高複合膜單電池操作溫度及性能。
另本研究將1.5 wt%的幾丁聚醣溶液複合上PTFE薄膜，做成PTFE/Chitosan複合膜，並測試複合膜浸泡不同的酸鹼種類製成MEA之燃料電池效能。其中浸漬H2SO4之PTFE/Chitosan複合膜，開路電位可達到0.86V，然而因為膜材本身機械強度及阻抗問題，電流仍無法測出。

關鍵字

四乙基矽烷；磷酸鋯；高溫燃料電池；幾丁聚醣

並列摘要

PTFE/Nafion-SiO2 and PTFE/Nafion-Zr(HPO4)2 composite membranes were prepared by impregnation of PTFE/Nafion composite membranes into TEOS and Zr(HPO4)2 solutions.
The PTFE/Nafion-SiO2 and PTFE/Nafion-Zr(HPO4)2 composite membranes have higher conductivity than PTFE/Nafion composite membrance of high temperature(above 100℃).
The results showed the performance of H2/O2 PEMFC based on PTFE/Nafion-Zr(HPO4)2 was better than that of H2/O2 PEMFC based on PTFE/Nafion-SiO2. At 110℃~130 ℃and 28.8%~51.7%RH, the current density of PTFE/Nafion-Zr(HPO4)2 composite membranes were 600 mA/cm2~1200 mA/cm2 ; the current density of PTFE/Nafion-SiO2 composite membranes were 600 mA/cm2~800 mA/cm2 . They both higher than the current density of Nafion 212 which was 300 mA/cm2~600 mA/cm2.
PTFE/Chitosan composite membranes were prepared by immersed in 1.5 wt% chitosan solution. Because of the strength and the resistence of the PTFE/Chitosan composite membranes, We can’t analyze the current of the fuel cell.

並列關鍵字

Tetraethoxysilane ； Zr(HPO4)2 ； High temperature fuel cell ； chitosan

參考文獻

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