The Effect of Cross-linking Technique on Membrane Performance for Direct Methanol Alkaline Fuel Cell Application

Öz

In this study, anion exchange membranes (AEM) based on poly(vinyl alcohol) (PVA) were prepared by two different cross-linking techniques and the effects of application sequence of thermal and chemical cross-linking technique on properties of AEM were investigated. Poly(ethylene glycol) diglycidly ether (PEGDGE) was used as a chemical cross-linking agent instead of the commonly used glutaraldehyde (GA). Evaluation of the fuel cell-related properties of the prepared membranes showed that the technique of cross-linking and the application sequence of techniques affected the properties of membranes. Promisingly, it was found that the membranes prepared by firstly chemical cross-linking and then thermal cross-linking at 150˚C (PPP150) exhibited high ionic conductivity (47 mS/cm), membrane selectivity values (89 x10⁴ S.s/cm³) and sufficient mechanical strength. These encouraging results indicate that AEMs-based on PVA cross-linked by chemical technique with PEGDGE and then thermal technique may be considered as a promising membrane for Direct Methanol Alkaline Fuel Cell (DMFC) applications.

Anahtar Kelimeler

• Fuel cell,Poly(vinyl alcohol),Crosslinking

Doğrudan Metanol Alkali Yakıt Hücresi Uygulamaları İçin Çapraz Bağlama Yönteminin Membran Performansı Üzerine Etkisi

Öz

Bu çalışmada poli (vinil alkol) (PVA) esaslı anyon değişim membranlar (AEM) iki farklı çapraz bağlama tekniği ile hazırlanmış ve ısıl ve kimyasal çapraz bağlama tekniklerinin uygulanma sırasının AEM’ın özellikleri üzerine etkisi incelenmiştir. Kimyasal çapraz bağlayıcı olarak en çok kullanılmakta olan glutaraldehit (GA) yerine poli(etilen glikol) diglisidil eter (PEGDGE) kullanılmıştır. Hazırlanan membranların yakıt hücresi ile ilgili özellikleri değerlendirildiğinde, çapraz bağlama tekniğinin ve farklı tekniklerin uygulama sırasının membranın özelliklerini etkilediği görülmüştür. Önce kimyasal sonra 150˚C’de ısıl çapraz bağlama uygulanarak hazırlanan membranın (PPP150) yüksek iyonik iletkenlik (47 mS/cm), membran seçimlilik (89 x10⁴ S.s/cm³)  ve yeterli mekanik dayanıma sahip olduğu görülmüştür. Elde edilen sonuçlar, önce PEGDGE ile kimyasal, sonra ısıl olarak çapraz bağlanan PVA esaslı anyon değişim membranların Doğrudan Metanol Alkali Yakıt Hücresi (DMFC) uygulamaları için ümit veren membranlar olarak düşünülebileceğini göstermiştir.

Anahtar Kelimeler

• Polivinil alkol,Yakıt hücresi,Çapraz bağlama

Kaynakça

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