20.500.12556/RUL-153024 Thermoelectric properties of pseudobrookite-based ceramics prepared from natural Fe-Ti-rich heavy mineral sand concentrate Pseudobrookites (Fe$_2$TiO$_5$-FeTi$_2$O$_5$) are promising candidates for high-temperature oxide thermoelectrics. In this work, we used natural Fe-Ti-rich heavy mineral sand (HMS) as an abundant and environmentally friendly raw material for the preparation of pseudobrookite-based ceramics. The main components of the initial powder were ilmenite (FeTiO$_3$) and pseudorutile (Fe$_2$Ti$_3$O$_9$) with various degrees of alteration. Pre-oxidation of the as-received powder was used for modification of the Fe$^{2+}$:Fe$^{3+}$ ratio and exsolution of rutile. The starting powders were densified by conventional sintering (CS; 1200 °C, 5 h, pressureless) and spark plasma sintering (SPS; 1100 °C, 5 min, 150 MPs) in argon. The thermoelectric properties of the sintered compacts depend mainly on the Fe:Ti ratio, the Fe$^{2+}$:Fe$^{3+}$ ratio, and the fraction and distribution of rutile in the microstructures. The samples exhibit comparable properties as the pseudobrookite-based ceramics prepared from high-purity chemicals indicating that, with some further optimization, natural Fe-Ti-rich HMS are an interesting alternative for the preparation of pseudobrookite-based ceramics for thermoelectric applications. Fe-Ti-rich heavy mineral sands natural raw materials Fe$_2$TiO$_5$ FeTi$_2$O$_5$ processing microstructure Fe$^{2+}$:Fe$^{3+}$ ratio thermoelectric characteristics true false true Angleški jezik Ni določen Članek v reviji 2023-12-14 14:37:28 2023-12-14 14:37:29 2023-12-15 03:49:27 0000-00-00 00:00:00 2023 0 0 Str. 7499-7507 iss. 16 Vol. 43 2023 0000-00-00 Zaloznikova Objavljeno NiDoloceno 0000-00-00 0000-00-00 0000-00-00 666 0955-2219 10.1016/j.jeurceramsoc.2023.07.071 160364803 1-s2.0-S095522192300599X-main.pdf 1-s2.0-S095522192300599X-main.pdf 1 09094E5C25C8796285836C31243AB849 6235d540a9f98fda69c7bf78a53c267e4cf7250a8bf2605546c8196f542eb3b2 35dafe5c-9a86-11ee-91f8-0050569b8976 https://repozitorij.uni-lj.si/Dokument.php?lang=slv&id=178810 https://www.sciencedirect.com/science/article/pii/S095522192300599X 0 0a45271d-9a86-11ee-91f8-0050569b8976 https://repozitorij.uni-lj.si/Dokument.php?lang=slv&id=178809 Naravoslovnotehniška fakulteta 0 0 0