Proton conductor NASICON-structure Li1+xCdx/2Zr2−x/2(PO4)3 as solid electrolyte for intermediate-temperature fuel cells

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A1 Alkuperäisartikkeli tieteellisessä aikakauslehdessä
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Journal of Materials Chemistry A, Volume 12, issue 8, pp. 4796-4805
Low ionic conductivity of solid electrolytes at intermediate temperatures hinders the commercialization process of solid fuel cell technology. A sodium superionic conductor (NASICON)-structure with a rigid three-dimensional network and an interconnected interstitial space is expected to be an ideal solid electrolyte for fuel cells. Based on the H+/Li+ exchange engineering strategy, here we report a NASICON-structure proton conductor Li1+xCdx/2Zr2−x/2(PO4)3 (x = 0.5, 1, 1.5, 2) derived from CdZr4(PO4)6 to construct a fuel cell device. Among all samples, the Li3Cd1Zr1(PO4)3 cell device exhibits a high performance including peak power density 815 mW cm−2, proton conductivity 0.165 S cm−1 and activation energy 0.372 eV at 550 °C. Theoretical and experimental studies both suggest that the high proton conductivity benefits from the unique 3D interstitial space and rapid H+/Li+ exchange in the NASICON material. Under fuel cell operating conditions, the interstitial space of Li1+xCdx/2Zr2−x/2(PO4)3 (x = 2) substitutes mobile Li+ with H+ enabling fast proton transport. The new transport mechanism and excellent proton conductivity suggest that Li1+xCdx/2Zr2−x/2(PO4)3 provides new opportunities for enriching novel electrolyte materials in intermediate temperature protonic ceramic fuel cells (IT-PCFCs).
Funding Information: This work was supported by the National Natural Science Foundation of China (NSFC) (Grant No. 22109022) and Postgraduate Research & Practice Innovation Program of Jiangsu Province (SJCX23_0061). Publisher Copyright: © 2024 The Royal Society of Chemistry.
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Li, X, Hu, E, Wang, F, Lund, P, Zhu, B & Wang, J 2024, ' Proton conductor NASICON-structure Li 1+x Cd x/2 Zr 2−x/2 (PO 4 ) 3 as solid electrolyte for intermediate-temperature fuel cells ', Journal of Materials Chemistry A, vol. 12, no. 8, pp. 4796-4805 .