Highly alkaline stability poly(aryl ether piperidinium) anion exchange membranes with partial aryl ether segments

• Published in: Chemical engineering journal (Lausanne, Switzerland : 1996) Vol. 471; p. 144547
• Main Authors: Liu, Jie, Gao, Li, Ruan, Xuehua, Zheng, Wenji, Yan, Xiaoming, He, Gaohong
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.09.2023
• Subjects: Anion exchange membranes; Chemical stability; Diphenyl ether; Fuel cells; Poly(aryl ether piperidinium); Anion exchange membranes; Poly(aryl ether piperidinium); Diphenyl ether; Chemical stability; Fuel cells
• ISSN: 1385-8947; 1873-3212
• DOI: 10.1016/j.cej.2023.144547

[Display omitted] •The poly(aryl ether piperidinium) membranes are prepared by super acid catalysis with less amount of catalyst.•The membrane shows the highest conductivity of 140 mS cm−1 and excellent stability of greater than 2000 h.•The fuel cell exhibits the highest peak power density of 1.2 W cm−2.•The polymers can be easily prepared into larger widths of membranes. Poly(aryl piperidinium) is considered a promising material for the preparation of anion exchange membranes (AEM) with considerable conductivity and excellent chemical stability for anion exchange membrane fuel cells (AEMFC). In this research, we report a range of biphenyl ether-containing poly(aryl ether piperidinium) unlike previous ones to increase the conductivity of AEMs and the peak power density (PPD) of fuel cells, and the alkaline stability of ether bonds in the polymer backbone is demonstrated. All of the poly(aryl ether piperidinium) membranes possess comparable mechanical properties and inherent viscosity derived from the high activity of biphenyl ethers in superacid-catalyzed reactions, which means that large-width AEMs can be prepared. The data demonstrated that the poly (ether p-terphenyl piperidinium) (QPEPTpi-35) exhibited a conductivity of 140 mS cm−1 at 80 ℃ compared to the original poly (p-terphenyl piperidinium) (QPTPpi) membrane owning to optimized micro-phase separation structure and higher water uptake. Meanwhile, QPEPTpi-35 membrane conductivity retention is greater than 85% after immersion in 1 M KOH for 2000 h at 80 ℃. Moreover, the PPD of the QPEPTpi-35 membrane reaches 1.2 W cm−2 in H2/O2 fuel cells, which is much higher than that of the QPTPpi membrane (0.51 W cm−2). The durability of MEA prepared by the catalyst-coated substrate (CCS) method manifests over 20 h under 0.2 A cm−2 at 60 °C.