Tripartite Cationic Interpenetrating Polymer Network Anion Exchange Membranes for Fuel Cells

Abstract

To facilitate large-scale commercial applications of anion exchange membrane fuel cells, high ionic conductivity and long-term durability of anion exchange membranes (AEMs) are crucial. Herein, poly(styrene-co-4-vinylbenzyl chloride) (PSVBC) without aryl ether linkages was synthesized by the radical bulk polymerization using styrene (St) and 4-vinylbenzyl chloride (VBC) as monomers. Then, using PSVBC as the framework material and secondary anion carrier, and polyquaternium-10 (PQ 10 ) as the main anion carrier, the tripartite cationic full-interpenetrating polymer network (F-IPN QPSVBC-PQ 10 ) AEMs were fabricated by the chemical crosslinking method. Upon preparation, the AEMs with distinctive nano-sized microphase separation can maintain a suitable swelling capability, assuring stable mechanical properties, dimensional stability, alkaline stability, and oxidation resistance, surpassing their semi-interpenetrating polymer network QPSVBC-PQ 10 AEM counterpart. Specifically, the ionic conductivity and peak power density of the optimally formulated AEM were 81.89 mS/cm and 119.31 mW/cm 2 , respectively. Meanwhile, 91.06% of the initial mass and 88.37% of the original ionic conductivity were maintained after successive 10-day oxidation test and 30-day alkali resistance test. In summary, the unique design of tripartite cationic F-IPN QPSVBC-PQ 10 AEMs without aryl ether linkages is undoubtedly beneficial to further promote the development of high-performance anion exchange membranes.

Semi-Interpenetrating Network Anion Exchange Membranes by Thiol–Ene Coupling Reaction for Alkaline Fuel Cells and Water Electrolyzers

“…AFM images provided in Figure S5a–d demonstrated that the microphase separation of the prepared QP-1/x AEMs is uniform and distinct. The darker regions represent the hydrophilic parts, whereas the lighter regions are the hydrophobic regions [ 25 ]. A more significant and denser microphase separation is observed in the QP-1/2 AEM ( Figure S5c ), promoting rapid ion transport, and thereby increasing the hydroxide ion conductivity.…”