Solid State Ionics, Vol.278, 144-151, 2015
Synthesis and characterization of novel anion exchange membranes containing bi-imidazolium-based ionic liquid for alkaline fuel cells
Novel anion-exchange membranes (AEMs) were prepared via in situ assembly of N-dodecyl-imidazole and 1,4-dibromobutane to construct the bi-imidazolium functionalized cationic liquid monomer, butanediyl-1,4-bis(N-dodecylimidazole bromide) into the isopropanol dispersions of quaternized chitosan, and followed by anion exchange with OH-. The morphology and characteristic properties of the resultant membranes, such as ion exchange capacity (IEC), anionic conductivity, and chemical stability were investigated. The membrane containing 15% mass fraction of butanediyl-1, 4-bis(N-dodecylimidazole bromide) shows that the anionic conductivity at 80 degrees C up to 41.9 mS cm(-1) and keep better long-term stability for 300 h in 1 mol dm(-3) KOH methanol solution than in 1 mol dm(-3) KOH aqueous solution. The introduction of hydrophobic alkyl side chain of the imidazole rings could drive the N+ ionic clusters to aggregate and promoting OH- mobility in AEMs. The results of this study suggest that the AEMs based on bi-imidazolium cations with long alkyl side chain have good perspectives for alkaline fuel cell application. (C) 2015 Elsevier B.V. All rights reserved.