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Proton-conducting membranes based on CsH2PO4 and copolymer of tetrafluoroethylene with vinylidene fluoride

Irina N. Bagryantseva, Yuri E. Kungurtsev, Valentina G. Ponomareva


In this work, proton conductivity, morphology and mechanical properties of (1–x)CsH2PO4–xF-42 (x=0.05–0.3, weight ratio) membranes were investigated for the first time. Thin flexible membranes for x≥0.15 with the uniform distribution of the components were obtained by a tape casting method. Mechanical properties of the membranes were measured by Vickers microhardness tests for a low polymer content (x˂0.15), also the tensile strength for membranes with high polymer content x=0.2–0.3 were evaluated. Proton conductivity of the (1–x)CsH2PO4–xpF-42 composite polymer electrolytes decreases monotonically with increasing x due to the effect of a «conductor-insulator» percolation. The combination of conductivity, mechanical strength and hydrophobic properties of (1–x)CsH2PO4–xF-42 makes certain compositions of proton-conducting membranes (x~0.2–0.25) promising for their use in intermediate-temperature fuel cells, despite decreased conductivity.


proton conductivity; cesium dihydrogen phosphate; fluoropolymer; p(VDF/TFE); tape casting

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Copyright (c) 2022 Irina N. Bagryantseva, Yuri E. Kungurtsev, Valentina G. Ponomareva

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Chimica Techno Acta, 2014-2024
ISSN 2411-1414 (Online)
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