Dual reinforced composite membranes from in-situ ionic crosslinked quaternized chitosan filled quaternized polyvinylidene fluoride nanofiber for alkaline direct methanol fuel cell

Ying Ou; Ting Qu; Fan Cheng; Haiyang Yang; Fuqiang Hu; Jie Wang; Hai Liu; Guoliang Liu; Sheng Wen; Chunli Gong

doi:10.1016/j.carbpol.2023.121363

Dual reinforced composite membranes from in-situ ionic crosslinked quaternized chitosan filled quaternized polyvinylidene fluoride nanofiber for alkaline direct methanol fuel cell

Carbohydr Polym. 2023 Dec 15:322:121363. doi: 10.1016/j.carbpol.2023.121363. Epub 2023 Sep 4.

Authors

Ying Ou¹, Ting Qu², Fan Cheng², Haiyang Yang², Fuqiang Hu², Jie Wang², Hai Liu³, Guoliang Liu⁴, Sheng Wen², Chunli Gong²

Affiliations

¹ Hubei Engineering & Technology Research Center for Functional Materials from Biomass, School of Chemistry and Material Science, Hubei Engineering University, Xiaogan, Hubei 432000, China. Electronic address: yingou@hbeu.edu.cn.
² Hubei Engineering & Technology Research Center for Functional Materials from Biomass, School of Chemistry and Material Science, Hubei Engineering University, Xiaogan, Hubei 432000, China.
³ Hubei Engineering & Technology Research Center for Functional Materials from Biomass, School of Chemistry and Material Science, Hubei Engineering University, Xiaogan, Hubei 432000, China. Electronic address: liuhai_218@hbeu.edu.cn.
⁴ State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Wuhan University of Technology, Nr. 122 Luoshi Rd., Wuhan 430070, China. Electronic address: liuguoliang@whut.edu.cn.

PMID: 37839835
DOI: 10.1016/j.carbpol.2023.121363

Abstract

The main obstacle of high-performance cationic functionalization chitosan (CS) as anion exchange membranes (AEMs) is the trade-off between mechanical stability and ionic conductivity. Here, in-situ ionic crosslinking between the deprotonated hydroxyl group and quaternary ammonium group under alkaline conditions was ingeniously applied to improve the mechanical stability of highly quaternized CS (HQCS) with high IEC (>2 mmol g^-1). Meanwhile, to further reduce the swelling and enhance the hydroxide conductivity, a mechanically robust hydroxide ion conduction network, quaternized electrospun poly(vinylidene fluoride) (QPVDF) nanofiber, was subsequently used as the filling substrate of in-situ crosslinked HQCS to prepare dual reinforced thin AEMs. The introduction of a robust QPVDF nanofiber mat can not only greatly improve the mechanical properties and limit swelling, but also create facile ion transport channels. Notably, the HQCS/QPVDF-74.0 composite membrane demonstrates perfect dimensional stability, high mechanical performance and excellent alkaline stability, as well as superior ionic conductivity of 66.2 mS cm^-1 at 80 °C. The thus assembled alkaline direct methanol fuel cell displays a maximum power density of 132.30 mW cm^-2 using 5 M KOH and 3 M methanol as fuels at 80 °C with satisfactory durability.

Keywords: Alkaline direct methanol fuel cells; Dual reinforced; In-situ ionic crosslinking; Quaternized chitosan; Quaternized electrospun poly(vinylidene fluoride).