TY - JOUR
T1 - Poly(Arylene Alkylene)s with Tetrazole Pendants for Alkaline Ion-Solvating Polymer Electrolytes
AU - Xia, Yifan
AU - Rajappan, Sinu C.
AU - Chen, Si
AU - Kraglund, Mikkel Rykær
AU - Serhiichuk, Dmytro
AU - Pan, Dong
AU - Jensen, Jens Oluf
AU - Jannasch, Patric
AU - Aili, David
N1 - Publisher Copyright:
© 2024 The Authors. ChemSusChem published by Wiley-VCH GmbH.
PY - 2024
Y1 - 2024
N2 - Alkaline ion-solvating membranes derived from a tetrazole functionalized poly(arylene alkylene) are prepared, characterized and evaluated as electrode separators in alkaline water electrolysis. The base polymer, poly[[1,1′-biphenyl]-4,4′-diyl(1,1,1-trifluoropropan-2-yl)], is synthesized by superacid catalyzed polyhydroxyalkylation and subsequently functionalized with tetrazole pendants. After equilibration in aqueous KOH, the relatively acidic tetrazole pendants are deprotonated to form the corresponding potassium tetrazolides. The room temperature ion conductivity is found to peak at 19 mS cm−1 in 5 wt. % KOH, and slightly declines with increasing KOH concentration to 13 mS cm−1 in 30 wt. % KOH. Based on an overall assessment of the mechanical properties, conductivity and electrode activity, 30 wt. % KOH is applied for alkaline electrolysis cell tests. Current densities of up to 1000 mA cm−2 were reached with uncatalyzed Ni-foam electrodes at a cell voltage of less than 2.6 V, with improved gas barrier characteristics compared to that of the several times thicker Zirfon separator.
AB - Alkaline ion-solvating membranes derived from a tetrazole functionalized poly(arylene alkylene) are prepared, characterized and evaluated as electrode separators in alkaline water electrolysis. The base polymer, poly[[1,1′-biphenyl]-4,4′-diyl(1,1,1-trifluoropropan-2-yl)], is synthesized by superacid catalyzed polyhydroxyalkylation and subsequently functionalized with tetrazole pendants. After equilibration in aqueous KOH, the relatively acidic tetrazole pendants are deprotonated to form the corresponding potassium tetrazolides. The room temperature ion conductivity is found to peak at 19 mS cm−1 in 5 wt. % KOH, and slightly declines with increasing KOH concentration to 13 mS cm−1 in 30 wt. % KOH. Based on an overall assessment of the mechanical properties, conductivity and electrode activity, 30 wt. % KOH is applied for alkaline electrolysis cell tests. Current densities of up to 1000 mA cm−2 were reached with uncatalyzed Ni-foam electrodes at a cell voltage of less than 2.6 V, with improved gas barrier characteristics compared to that of the several times thicker Zirfon separator.
KW - Ion-solvating membrane
KW - Alkaline water electrolysis
KW - Polyhydroxyalkylation
KW - Tetrazole functionalization
KW - Conductivity
U2 - 10.1002/cssc.202400844
DO - 10.1002/cssc.202400844
M3 - Journal article
C2 - 39115117
AN - SCOPUS:85200668522
SN - 1864-5631
VL - 17
JO - ChemSusChem
JF - ChemSusChem
IS - 23
M1 - e202400844
ER -