Indexed by:Journal Papers

Date of Publication:2019-10-31

Journal:JOURNAL OF POWER SOURCES

Included Journals:SCIE、EI

Volume:438

ISSN:0378-7753

Key Words:Fuel cells; Hydroxide exchange membrane; Symmetric piperazinium; Rigid side chain; Phase separation

Abstract:Developing anion exchange membranes (AEMs) having high hydroxide conductivity, swelling resistance and excellent alkaline stability is a challenge for fuel cells now. Herein, a universal and controllable approach of grafting rigid side chain is first proposed to construct connected ion transport nano-channels. A new route is also provided to prepare AEMs with stable symmetric saturated heterocyclic amomium. The rigid side chain is introduced onto poly(2,6-dimethyl-1,4-phenylene oxide) (PPO) by the Friedel-Crafts acylation with 4-fluorobenzoyl chloride and subsequent reaction between phenyl fluoride and secondary amine of 1-methylpiperazine. Then the terminal piperazinium is produced by the reaction between tertiary amine of 1-methylpiperazine and methyl iodide. Rigid branches expand free volume to construct connected ion transport nano-channels, leading to excellent conductivity (108 mS cm(-1) at 60 degrees C) that is higher than those of other reported symmetric heterocyclic amomium functionalized AEMs (33-89 mS cm(-1) at 60 degrees C). Due to the high conductivity, the H-2/O-2 cell employing this membrane achieves one of the highest peak power densities (1210 mW cm(-2) at 2600 mA cm(-2)) so far. In addition, the IEC of the membrane remains constant after testing in 1 M NaOH at 60 degrees C over 500 h.