2026-06-28T10:14:16Zhttps://docta.ucm.es/rest/oai/request

oai:docta.ucm.es:20.500.14352/937672025-09-02T15:00:32Zcom_20.500.14352_14col_20.500.14352_15

00925njm 22002777a 4500 dc Hudelja, Polona author Schmidt, Rainer author Amorín, Harvey author Drev, Sandra author Ivekovic, Aljaz author Abram, Anze author Kocjan, Andraz author Wicklein, Bernd author 2022 Ceramic matrix composites (CMC) of 8 mol.% yttria-stabilized zirconia (8YSZ) mixed with natural fiber nano cellulose (0.75, 1, 2 wt%) were prepared by spark plasma sintering (SPS). Nanocellulose markedly improved the densification of the 8YSZ ceramic matrix and induced significant grain size refinement. It was demonstrated that in situ graphitization of nanocellulose during the SPS processing resulted in 6 nm thin turbostratic graphite layers homogeneously covering the 8YSZ ceramic grains. The dielectric properties were analyzed by electrical impedance spectroscopy suggesting a low percolation threshold near or below asymptotic to 1.6 vol% graphite, above which mixed ionic-electronic conduction dominates. The CMCs are stable under reducing conditions (5%H-2/Ar atmosphere) at least until 800 ? with a high conductivity of sigma(dc) = 0.17 S center dot cm(-1) even at 900 ? (8YSZ-2%CNF). These features make the 8YSZ-nanocellulose CMCs promising candidates for application in medium-to high temperature electrochemical devices. Polona Hudelja, Rainer Schmidt, Harvey Amorín, Sandra Drev, Aljaž Iveković, Anže Abram, Andraž Kocjan, Bernd Wicklein, Microstructure-property relationships in composites of 8YSZ ceramics and in situ graphitized nanocellulose, Journal of the European Ceramic Society, Volume 42, Issue 11, 2022, Pages 4594-4606, ISSN 0955-2219, https://doi.org/10.1016/j.jeurceramsoc.2022.04.041. 0955-2219 10.1016/j.jeurceramsoc.2022.04.041 https://hdl.handle.net/20.500.14352/93767 https://doi.org/10.1016/j.jeurceramsoc.2022.04.041 Microstructure-property relationships in composites of 8YSZ ceramics and in situ graphitized nanocellulose