| DC 欄位 |
值 |
語言 |
| DC.contributor | 化學學系 | zh_TW |
| DC.creator | 黃奕雲 | zh_TW |
| DC.creator | Yi-Yun Huang | en_US |
| dc.date.accessioned | 2018-7-3T07:39:07Z | |
| dc.date.available | 2018-7-3T07:39:07Z | |
| dc.date.issued | 2018 | |
| dc.identifier.uri | http://ir.lib.ncu.edu.tw:88/thesis/view_etd.asp?URN=105223015 | |
| dc.contributor.department | 化學學系 | zh_TW |
| DC.description | 國立中央大學 | zh_TW |
| DC.description | National Central University | en_US |
| dc.description.abstract | 鹼性燃料電池因其可使用非白金觸媒，有望降低價格，為近年來再生能源研究發展的一大趨勢；然薄膜研究上仍欠缺足夠條件使其商業化，其中最需克服的為同時擁有良好的離子導電度以及較低的燃料竄透。
本研究係利用分歧狀雙馬來醯亞胺聚合物（mBMI）和聚乙烯醇（PVA）之間形成semi-IPN（半互穿網絡）結構所製備的薄膜以降低乙醇的竄透率。同時，由於PVA及mBMI本身帶有親水官能基且相鄰醯亞胺基之間有利於氫氧根離子的傳遞，使此薄膜在鹼性溶液（KOH）下的離子導電度能隨添加mBMI的含量增加而有所提升，達到良好的離子導電度；另外，隨著添加mBMI含量增加，半互穿網絡交聯程度上升亦能使薄膜膨潤程度下降。
此外，本研究另一重點為以外加電場極化的狀態下製備成膜，可以將薄膜內部電負度較大的原子(如：O、N等)暴露以增加親水官能基，同時形成有序的親水離子傳導通道使非結晶區更為緻密。相較於無電場極化下的複合薄膜，在外加電場極化下的mBMI/PVA複合薄膜顯示出更優異的OH- 離子導電率（1.20*10 -2 S / cm 至3.82*10 -2 S / cm）、更低的乙醇竄透性（3.61*10 -7 cm 2 / s至7.77*10 -8 cm2 / s）， 以及極高的選擇率 (將近4*105)；此外，電場極化產生更緻密膜材結構，亦提高了薄膜的化學穩定性以及機械強度。
本研究顯示以外加電場的方式製備成膜可以提升離子導電度、降低燃料竄透以提升薄膜的選擇率，並同時提升薄膜的機械強度以及化學穩定性等物性，在最後ADEFC單電池測試中，薄膜亦相較於文獻中PVA薄膜有更卓越的表現，其電流密度達225 mA/cm2、功率密度達48 mA/cm2，顯示此類型薄膜可有效應用於鹼性燃料電池中。 | zh_TW |
| dc.description.abstract | A new category of hydroxide ion exchange membrane bearing ordered interpenetrating network (semi-IPN) structure established by electric field poling during membrane formation, lead to balanced property where high ion conductivity and low alcohol (methanol and ethanol) permeability co-existed. Success of this membrane preparation scheme is illustrated with the semi-IPN membrane formed by dendritic modified bismaleimide (mBMI) and polyvinyl alcohol (PVA) hydrogel casted together under applied electric field (E-field> 2000V/cm, Ac=1-20Hz,). Detailed morphology and water diffusion studies shows electric field poling establishes higher ordered amorphous domains that induces preferentially oriented conducting path that raised ion conductivity. On the other hand, semi-IPN network effectively reduces methanol and ethanol permeation and improves membrane toughness. When PVA:mBMI equals 2 to 3 weight ratio, the membrane delivered impressive room temperature OH ion conductivity of 38.2 mS/cm and a substantially reduced ethanol permeation of 7.7x10-8 cm2/s; giving exceedingly high ethanol selectivity ratio (>105) with electric field poling preparation. Ordering in the semi-IPN structure by electric field poling also causses densification of the amorphous domain that leads to improved chemical stability (99wt% mass retention in 6M KOH for nearly a month) and mechanical toughness (Tensile strength increased from 3.5 MPa to 7.0 MPa, and elongation at break raised from 60% to 92%). The study concludes the application of an external electric field initiated reorganization of membrane morphology where high performance fuel cell membrane bearing high ion conductivity; low fuel permeation; high membrane strength; and high chemical stability can be established, simultaneously. | en_US |
| DC.subject | 燃料電池 | zh_TW |
| DC.title | 電場誘導聚乙烯醇改質雙馬來醯亞胺複合薄膜於鹼性直接乙醇燃料電池之應用 | zh_TW |
| dc.language.iso | zh-TW | zh-TW |
| DC.type | 博碩士論文 | zh_TW |
| DC.type | thesis | en_US |
| DC.publisher | National Central University | en_US |