Robust anion conductive polymers containing perfluoroalkylene and pendant ammonium groups for high performance fuel cells. Issue 47 (21st November 2017)

• Record Type: Journal Article
• Authors: Ono, Hideaki; Kimura, Taro; Takano, Aoi; Asazawa, Koichiro; Miyake, Junpei; Inukai, Junji; Miyatake, Kenji
• Is Part Of: Journal of materials chemistry. Volume 5:Issue 47(2017)
• Page Start: 24804
• Page End: 24812
• Publication Date: 2017-11-21
• Subjects: Materials -- Research -- Periodicals; Chemistry, Analytic -- Periodicals; Environmental sciences -- Research -- Periodicals; 543.0284
• DOI: 10.1039/c7ta09409d
• Languages: English
• ISSNs: 2050-7488

Abstract

Abstract : Well-designed ammonium-functionalized polymers achieved high performance and durability in hydrazine alkaline fuel cells. Abstract : A novel series of ammonium-containing copolymers (QPAF-4) were designed and synthesized as anion exchange membranes for alkaline fuel cell applications. The copolymers were prepared via a nickel promoted polycondensation reaction with high molecular weights ( M w = 72.7–276.4 kDa as precursors) and were composed of perfluoroalkylene and fluorenyl groups with pendant ammonium groups. The QPAF-4 membrane with optimized copolymer composition and ion exchange capacity exhibited high hydroxide ion conductivity (86.2 mS cm −1 in water at 80 °C) and excellent mechanical properties (large elongation at break = 269%). A severe alkaline stability test of the QPAF-4 membranes in 1 M KOH at 80 °C for 1000 h and the post-test analyses of the 1 H NMR spectra, solubility, and mechanical properties revealed minor, or no, changes in the chemical structure and properties. Alkaline fuel cells using the QPAF-4 membrane were operated using hydrazine as a fuel and oxygen or air as oxidant to achieve the high maximum power density of 515 mW cm −2 . The durability of the membrane was also confirmed in the operating fuel cell at a constant current density for longer than 1000 h.