79063 20240104111807.0 doi 10.1016/j.ceramint.2018.04.071 sideral 105813 ART-2018-105813 eng Sotelo, A. Universidad de Zaragoza (orcid)0000-0001-7056-0546 Effect of simultaneous K, and Yb substitution for Ca on the microstructural and thermoelectric characteristics of CaMnO3 ceramics 2018 Access copy available to the general public Unrestricted CaMnO3-based materials are very attractive among n-type thermoelectric oxides for high-temperature applications when they are appropriately doped. The main drawback of these materials is the cost associated to the necessary rare earth cations. This work aims decreasing the amount of these materials through a partial substitution of Ca2+ by an equimolar mixture of K+ and Yb3+, Ca1-x(K0.5Yb0.5)xMnO3, with x = 0.05, 0.10, 0.15, and 0.20. XRD studies have confirmed that the thermoelectric phase is the major one in all samples. Microstructure has shown the formation of large crystals, and an increasing porosity when the substitution is raised. This evolution has been confirmed through density measurements. Electrical resistivity has been drastically decreased for the 0.10 substituted samples, compared with the 0.05 ones, slightly increasing for higher substitution. On the other hand, absolute Seebeck coefficient and thermal conductivity are lower when the substitution is raised. The best ZT values have been achieved for the 0.10 substituted samples, which are around the typical reported in the literature for higher doping level. These results clearly point out to a decrease of the necessary rare earth dopant content to achieve similar performances in CaMnO3 ceramics, which is of the main economic significance for their industrial production. info:eu-repo/grantAgreement/ES/DGA-FEDER/T12 info:eu-repo/grantAgreement/ES/DGA-FEDER/T87 info:eu-repo/grantAgreement/ES/MINECO-FEDER/MAT2017-82183-C3-1-R info:eu-repo/grantAgreement/ES/UZ/UZ2017-TEC-03 info:eu-repo/semantics/openAccess by-nc-nd http://creativecommons.org/licenses/by-nc-nd/3.0/es/ 3.45 2018 MATERIALS SCIENCE, CERAMICS 2 / 28 = 0.071 2018 Q1 T1 0.888 2018 Electronic, Optical and Magnetic Materials 2018 Q1 Ceramics and Composites 2018 Q1 Surfaces, Coatings and Films 2018 Q1 Process Chemistry and Technology 2018 Q1 Materials Chemistry 2018 Q1 info:eu-repo/semantics/article info:eu-repo/semantics/acceptedVersion Depriester, M. Torres, M.A. Universidad de Zaragoza (orcid)0000-0003-3995-5763 Sahraoui, A.H. Madre, M.A. Universidad de Zaragoza (orcid)0000-0002-0794-3998 Diez, J.C. Universidad de Zaragoza (orcid)0000-0001-9995-6368 5002 305 Universidad de Zaragoza Dpto. Ingeniería Diseño Fabri. Área Expresión Gráfica en Ing. 5001 065 Universidad de Zaragoza Dpto. Ciencia Tecnol.Mater.Fl. Área Cienc.Mater. Ingen.Metal. 44, 11 (2018), 12697-12701 Ceram. int. Ceramics International 0272-8842 184132 http://zaguan.unizar.es/record/79063/files/texto_completo.pdf Postprint 94218 http://zaguan.unizar.es/record/79063/files/texto_completo.jpg?subformat=icon icon Postprint oai:zaguan.unizar.es:79063 articulos driver 2024-01-04-11:00:50 ARTICLE