TY - JOUR
T1 - Optimization of the pendant chain length in partially fluorinated aromatic anion exchange membranes for alkaline fuel cells
AU - Ahmed Mahmoud, Ahmed Mohamed
AU - Miyatake, Kenji
N1 - Funding Information:
This work was partly supported by CREST (JPMJCR12C3), Japan Science and Technology (JST) Agency and the Ministry of Education, Culture, Sports, Science and Technology (MEXT) Japan through a Grant-in-Aid for Scientic Research (18H02030). K.M. acknowledges the Ogasawara Foundation for the Promotion of Science and Engineering for nancial support. We thank Mr Taro Kimura for SAXS measurements and Mr Kanji Otsuji for fuel cell experiments.
Funding Information:
This work was partly supported by CREST (JPMJCR12C3), Japan Science and Technology (JST) Agency and the Ministry of Education, Culture, Sports, Science and Technology (MEXT) Japan through a Grant-in-Aid for Scientific Research (18H02030). K.M. acknowledges the Ogasawara Foundation for the Promotion of Science and Engineering for financial support.
Publisher Copyright:
© 2018 The Royal Society of Chemistry.
PY - 2018
Y1 - 2018
N2 - For robust anion exchange membranes, we have investigated the effect of aliphatic side chains on the properties of partially fluorinated aromatic copolymers (QPAFs) with ammonium groups. A new series of QPAF membranes with various interstitial aliphatic side chain lengths (QPAF-Cx) where x = 2-6 were successfully synthesized. QPAF-C3 with a propylene side chain and ion exchange capacity (IEC = 1.24 meq. g-1) showed balanced properties with the highest hydroxide ion conductivity (99 mS cm-1 at 80 °C in water) and relatively low water uptake, based on a well-developed phase separated morphology. Moreover, the QPAF-C3 membrane exhibited excellent alkaline stability to maintain high ion conductivity (98% remaining) and high mechanical properties after 1000 h in 1 M KOH at 80 °C. The QPAF-C3 membrane also revealed reasonable stability even in 4 M and 8 M KOH at 80 °C. In fuel cell operation, the QPAF-C3 membrane exhibited a higher power density (224 mW cm-2) than those of our previous QPAF-C1 (138 mW cm-2), QPAF-C1B (167 mW cm-2), and Tokuyama A-201 (122 mW cm-2) membranes. In the durability test for 62 h, QPAF-C3 maintained 69% of its initial voltage with minor structural degradation.
AB - For robust anion exchange membranes, we have investigated the effect of aliphatic side chains on the properties of partially fluorinated aromatic copolymers (QPAFs) with ammonium groups. A new series of QPAF membranes with various interstitial aliphatic side chain lengths (QPAF-Cx) where x = 2-6 were successfully synthesized. QPAF-C3 with a propylene side chain and ion exchange capacity (IEC = 1.24 meq. g-1) showed balanced properties with the highest hydroxide ion conductivity (99 mS cm-1 at 80 °C in water) and relatively low water uptake, based on a well-developed phase separated morphology. Moreover, the QPAF-C3 membrane exhibited excellent alkaline stability to maintain high ion conductivity (98% remaining) and high mechanical properties after 1000 h in 1 M KOH at 80 °C. The QPAF-C3 membrane also revealed reasonable stability even in 4 M and 8 M KOH at 80 °C. In fuel cell operation, the QPAF-C3 membrane exhibited a higher power density (224 mW cm-2) than those of our previous QPAF-C1 (138 mW cm-2), QPAF-C1B (167 mW cm-2), and Tokuyama A-201 (122 mW cm-2) membranes. In the durability test for 62 h, QPAF-C3 maintained 69% of its initial voltage with minor structural degradation.
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U2 - 10.1039/c8ta04310h
DO - 10.1039/c8ta04310h
M3 - Article
AN - SCOPUS:85050515064
SN - 2050-7488
VL - 6
SP - 14400
EP - 14409
JO - Journal of Materials Chemistry A
JF - Journal of Materials Chemistry A
IS - 29
ER -
