An enhanced thermoelectric figure of merit for Sr(Ti0.8Nb0.2)O3 based on a Ruddlesden–Popper-polytype-induced microstructure. Issue 5 (April 2016)

• Record Type: Journal Article
• Authors: Jerič, Marja; de Boor, Johannes; Jančar, Boštjan; Čeh, Miran
• Is Part Of: Journal of the European Ceramic Society. Volume 36:Issue 5(2016:)
• Page Start: 1177
• Page End: 1182
• Publication Date: 2016-04
• Subjects: Thermoelectric materials -- Nb-doped SrTiO3 -- Ruddlesden–Popper polytypes -- Seed crystals -- Molten-salt synthesis; Ceramic materials -- Periodicals; Composite materials -- Periodicals; Matériaux céramiques -- Périodiques; Composites -- Périodiques; Ceramic materials; Composite materials; Periodicals; Electronic journals; 666.05
• DOI: 10.1016/j.jeurceramsoc.2015.12.001
• Languages: English
• ISSNs: 0955-2219

Abstract

Abstract: Platelet crystals based on Ruddlesden–Popper (RP) polytypes prepared by molten-salt synthesis were used to influence the microstructural development of Nb-doped SrTiO3 (STO;Nb) perovskite and, consequently, to change the thermoelectric properties. Electron microscopy revealed intergrowth of RP-polytypic phases within the STO;Nb solid-solution matrix phase. The morphology of the grains varied from isotropic to anisotropic, containing polytypic faults up to 100 μm in length. Such a microstructure increased the thermoelectric figure of merit by 50% at 650 °C, due to substantially enhanced electrical conductivity, slightly increased Seebeck coefficient and lowered thermal conductivity.