Aggregated and ionic cross-linked anion exchange membrane with enhanced hydroxide conductivity and stability

• Published in: Journal of power sources Vol. 459; p. 227838
• Main Authors: Han, Juanjuan, Lin, Bencai, Peng, Hanqing, Zhu, Yuchan, Ren, Zhandong, Xiao, Li, Zhuang, Lin
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 31.05.2020
• Subjects: High hydroxide conductivity; High stability; Ionic cross-linking; Microphase separation; Quaternary ammonia polysulfone; Microphase separation; High hydroxide conductivity; Quaternary ammonia polysulfone; High stability; Ionic cross-linking
• ISSN: 0378-7753; 1873-2755
• DOI: 10.1016/j.jpowsour.2020.227838

In order to achieve a better trade-off among ionic conductivity, mechanical strength and chemical stability, a series of novel aggregated and ionic cross-linked anion exchange membranes (AEMs) are recommended, namely, acS6QAPSF, acS8QAPSF and acS10QAPSF. Cross-linked network shoulders the responsibility to toughen the acSxQAPSF. Appropriate micro-morphology is responsible for facilitating the conduction of OH− and improving the alkaline stability of the acSxQAPSF. Compared with the original QAPSF, acSxQAPSF membranes exhibit much better properties. Specifically, for acS8QAPSF, a high OH− conductivity of 90.5 mS cm−1 is achieved at 80 °C, with the swelling degree of 10.0%. The tensile strength and elongation at break of wet acS8QAPSF at 25 °C are 23.9 Mpa and 21.1%, respectively. After testing in 1 M NaOH at 80 °C for 30 days, the weight loss of acS8QAPSF is 8.0%, with the losses of tensile strength and elongation at break of 13.8% and 13.3%, respectively. Its IEC and IC retentions are 92.0% and 90.5%, respectively. For acS8QAPSF, a fuel cell peak power density of 0.612 W cm−2 is obtained at 60 °C. While for QAPSF, its fuel cell peak power density is only 0.101 W cm−2, and the film is cracked after the 30 days stability test. The unique acSxQAPSF membrane can alleviate the tradeoff among ionic conductivity, mechanical strength and chemical stability. [Display omitted] •Novel aggregated and ionic cross-linked AEMs based on PSF are synthesized.•An important insight into the design of AEMs with high performance is provided.•The fuel cell of acS8QAPSF achieved a peak power density of 612 mW cm−2 at 60 °C.