Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
7739820 | Journal of Power Sources | 2013 | 9 Pages |
Abstract
The novel, low-cost anion-exchange membranes (abbreviated as PVA/PDDA-OHâ), made from poly(vinyl alcohol) and poly(diallyldimethylammonium chloride) blends, are successfully synthesized by a combined thermal and chemical cross-linking technique. The hydroxide (OHâ) conductivity, water uptake, ion exchange capacity (IEC), thermal stability, oxidative stability and alkaline stability of PVA/PDDA-OHâ membranes are measured to evaluate their applicability in alkaline fuel cells. The effects of cross-linking procedure, cross-linking time and membrane composition on OHâ conductivity are studied using AC impedance technique. It is found that by cross-linking modifications, the membranes exhibit excellent thermal stability with onset degradation temperature high above 170 °C, a relatively high oxidative stability at 60 °C, and a strong alkaline stability in 8 M KOH at 80 °C. High OHâ conductivity of 0.025 S cmâ1 is achieved at 25 °C and reaches up to 0.037 S cmâ1 at 80 °C. For exploring the conducting mechanisms, the concentration and mobility of charge carries of the membranes are also measured. The H2/O2 fuel cell tests with PVA/PDDA-OHâ membranes yield the peak power density of 11.5 mW cmâ2 and greatly increase to 35.1 mW cmâ2 depending on PVA/PDDA mass ratio, on a low metal loading on both the anode and the cathode of 0.5 mg (Pt) cmâ2 at ambient temperature.
Keywords
Related Topics
Physical Sciences and Engineering
Chemistry
Electrochemistry
Authors
Jing Zhang, Jinli Qiao, Gaopeng Jiang, Lingling Liu, Yuyu Liu,