Poly(p-terphenyl-piperidine-bromoacetophenone) anion exchange membranes with pendant N-spirocyclic cations: Cations synergistic build efficient ion transport networks

Abstract

The establishment of well-developed ionic conduction channels and the preparation of excellent chemical stability are urgent needs for anion exchange membranes. In this study, we successfully prepared poly (p-terphenyl-piperidine-bromoacetophenone) polymers using superacid catalysis. Then a series of QPTPP-N-ASU-x AEMs were prepared by introducing N-spirocyclic side chain cations (N-ASU) with different grafting rates. The introduction of N-spirocyclic cations with better alkali resistance increases multiple OH− transport sites, contributes to the microphase separation structure, and is synergistic with piperidine cations to rapidly construct ion transport networks, giving the membranes good conductivity and alkali resistance stability. The AFM showed that QPTPP-N-ASU-5% AEM had a remarkable microstructure and formed large ionic domains, the conductivity of the membrane was 121.2 mS cm−1, corresponding to a peak power density of 477.25 mW cm−2. The conductivity residual of QPTPP-N-ASU-5% AEM was 94.15 % and 87.71 % after immersion in 2 M and 4 M NaOH at 80 °C for 1440 h. It shows that membrane has good potential for application.