High-performance anion exchange membranes based on poly(oxindole benzofuran dibenzo-18-crown-6)s functionalized with hydroxyl and quaternary ammonium groups for alkaline water electrolysis
Wang, Qian ; Wei, Tao ; Peng, Zhen ; Zhao, Yun ; Jannasch, Patric LU
and Yang, Jingshuai
LU
(2025)
In Journal of Colloid and Interface Science
686.
p.304-317
- Abstract
- Anion exchange membranes (AEMs) play a vital role in AEM water electrolysis (AEMWE), a promising technology for hydrogen production. However, it remains challenging to develop AEMs that simultaneously achieve high OH− conductivity, robust alkaline stability, and sustained operational performance in AEMWE. In the present study, we report on a class of high-performance, readily synthesized AEMs based on poly(oxindole benzofuran dibenzo-18-crown-6)s functionalized with hydroxyl and quaternary ammonium groups. A super-acid-catalyzed Friedel-Crafts reaction was used to copolymerize dibenzofuran (DBF), dibenzo-18-crown-6 (DBC) and isatin to yield a series of poly(oxindole benzofuran dibenzo-18-crown-6)s (P(O-Fx-Cy)s). The hydrophilic... (More)
- Anion exchange membranes (AEMs) play a vital role in AEM water electrolysis (AEMWE), a promising technology for hydrogen production. However, it remains challenging to develop AEMs that simultaneously achieve high OH− conductivity, robust alkaline stability, and sustained operational performance in AEMWE. In the present study, we report on a class of high-performance, readily synthesized AEMs based on poly(oxindole benzofuran dibenzo-18-crown-6)s functionalized with hydroxyl and quaternary ammonium groups. A super-acid-catalyzed Friedel-Crafts reaction was used to copolymerize dibenzofuran (DBF), dibenzo-18-crown-6 (DBC) and isatin to yield a series of poly(oxindole benzofuran dibenzo-18-crown-6)s (P(O-Fx-Cy)s). The hydrophilic and π-conjugated DBF units endow the membranes with additional free volume, while bulky DBC units promote a favorable microphase separated morphology and impart resistance to hydroxide attack. Quaternization is achieved via a ring-opening reaction with glycidyl trimethyl ammonium chloride (GTA) without requiring a basic catalyst. The resulting side chains, featuring alkyltrimethylammonium cations with hydroxyl groups in the β-position, introduce hydrogen-bonding networks and enhance OH− conductivity. The optimized P(O-F50%-C50%)-GTA membrane exhibits a well-developed microphase separated structure, achieving Cl− conductivity of up to 102 mS cm−2 at 80 °C. Moreover, the presence of DBC groups mitigates degradation of the hydroxyl-containing side chains, enabling the membrane to retain 81 % of its original conductivity after 600 h of alkaline stability testing in 1 M KOH at 80 °C. In a PGM-free AEMWE, the P(O-F50%-C50%)-GTA membrane attains a current density of 3.8 mA cm−2 at 2 V and 80 °C. These findings underscore the potential of incorporating DBF and DBC moieties in the polymer main chain, along with the GTA-functionalized side chains, offering a promising pathway for advancing AEMs in AEMWE applications.
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Please use this url to cite or link to this publication:
https://lup.lub.lu.se/record/a2aced37-188c-4c39-8d58-a94312e4dc5b
- author
- Wang, Qian
; Wei, Tao
; Peng, Zhen
; Zhao, Yun
; Jannasch, Patric
LU
and Yang, Jingshuai
LU
- organization
- publishing date
- 2025
- type
- Contribution to journal
- publication status
- published
- subject
- in
- Journal of Colloid and Interface Science
- volume
- 686
- pages
- 14 pages
- publisher
- Academic Press
- external identifiers
-
- scopus:85216595988
- pmid:39903978
- ISSN
- 0021-9797
- DOI
- 10.1016/j.jcis.2025.01.244
- language
- English
- LU publication?
- yes
- id
- a2aced37-188c-4c39-8d58-a94312e4dc5b
- date added to LUP
- 2025-01-28 14:53:56
- date last changed
- 2025-04-30 03:00:02
@article{a2aced37-188c-4c39-8d58-a94312e4dc5b,
abstract = {{Anion exchange membranes (AEMs) play a vital role in AEM water electrolysis (AEMWE), a promising technology for hydrogen production. However, it remains challenging to develop AEMs that simultaneously achieve high OH<sup>−</sup> conductivity, robust alkaline stability, and sustained operational performance in AEMWE. In the present study, we report on a class of high-performance, readily synthesized AEMs based on poly(oxindole benzofuran dibenzo-18-crown-6)s functionalized with hydroxyl and quaternary ammonium groups. A super-acid-catalyzed Friedel-Crafts reaction was used to copolymerize dibenzofuran (DBF), dibenzo-18-crown-6 (DBC) and isatin to yield a series of poly(oxindole benzofuran dibenzo-18-crown-6)s (P(O-Fx-Cy)s). The hydrophilic and π-conjugated DBF units endow the membranes with additional free volume, while bulky DBC units promote a favorable microphase separated morphology and impart resistance to hydroxide attack. Quaternization is achieved via a ring-opening reaction with glycidyl trimethyl ammonium chloride (GTA) without requiring a basic catalyst. The resulting side chains, featuring alkyltrimethylammonium cations with hydroxyl groups in the β-position, introduce hydrogen-bonding networks and enhance OH<sup>−</sup> conductivity. The optimized P(O-F50%-C50%)-GTA membrane exhibits a well-developed microphase separated structure, achieving Cl<sup>− </sup>conductivity of up to 102 mS cm<sup>−2</sup> at 80 °C. Moreover, the presence of DBC groups mitigates degradation of the hydroxyl-containing side chains, enabling the membrane to retain 81 % of its original conductivity after 600 h of alkaline stability testing in 1 M KOH at 80 °C. In a PGM-free AEMWE, the P(O-F50%-C50%)-GTA membrane attains a current density of 3.8 mA cm<sup>−2</sup> at 2 V and 80 °C. These findings underscore the potential of incorporating DBF and DBC moieties in the polymer main chain, along with the GTA-functionalized side chains, offering a promising pathway for advancing AEMs in AEMWE applications.<br/>}},
author = {{Wang, Qian and Wei, Tao and Peng, Zhen and Zhao, Yun and Jannasch, Patric and Yang, Jingshuai}},
issn = {{0021-9797}},
language = {{eng}},
pages = {{304--317}},
publisher = {{Academic Press}},
series = {{Journal of Colloid and Interface Science}},
title = {{High-performance anion exchange membranes based on poly(oxindole benzofuran dibenzo-18-crown-6)s functionalized with hydroxyl and quaternary ammonium groups for alkaline water electrolysis}},
url = {{http://dx.doi.org/10.1016/j.jcis.2025.01.244}},
doi = {{10.1016/j.jcis.2025.01.244}},
volume = {{686}},
year = {{2025}},
}