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Journal of Thermal Analysis and Calorimetry
Authors: Mary Alves, Soraia Souza, Márcia Silva, Elaine Paris, S. Lima, R. Gomes, E. Longo, A. de Souza, and Iêda Garcia dos Santos

Abstract  

SrSnO3 was synthesized by the polymeric precursor method with elimination of carbon in oxygen atmosphere at 250 °C for 24 h. The powder precursors were characterized by TG/DTA and high temperature X-ray diffraction (HTXRD). After calcination at 500, 600 and 700 °C for 2 h, samples were evaluated by X-ray diffraction (XRD), infrared spectroscopy (IR) and Rietveld refinement of the XRD patterns for samples calcined at 900, 1,000 and 1,100 °C. During thermal treatment of the powder precursor ester combustion was followed by carbonate decomposition and perovskite crystallization. No phase transition was observed as usually presented in literature for SrSnO3 that had only a rearrangement of SnO6 polyhedra.

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Journal of Thermal Analysis and Calorimetry
Authors: F. T. G. Vieira, A. L. M. Oliveira, D. S. Melo, S. J. G. Lima, E. Longo, A. S. Maia, A. G. Souza, and I. M. G. Santos

due to its use as humidity sensor [ 3 ]. The interest in SrSnO 3 compounds is related to its hability for Fe doping, formation of vacancies, besides oxidation or reduction of Fe 3+ contribute to the stabilization of the perovskite phase [ 2 , 4 , 5

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Journal of Thermal Analysis and Calorimetry
Authors: D. Melo, R. M. M. Marinho, F. T. G. Vieira, S. J. G. Lima, E. Longo, A. G. Souza, A. S. Maia, and I. M. G. Santos

H 2 O, and catalysts for reduction in the amount of pollutants as NO x [ 5 , 6 ]. One of the most important stannates is strontium stannate (SrSnO 3 ) that presents the orthorhombic perovskite structure (Pbnm space group) at room temperature with

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Journal of Thermal Analysis and Calorimetry
Authors: Soraia de Souza, Mary Alves, A. de Oliveira, E. Longo, F. Ticiano Gomes Vieira, Rodinei Gomes, L. Soledade, A. de Souza, and Iêda Garcia dos Santos

Abstract  

In this work, the synthesis of Nd-doped SrSnO3 by the polymeric precursor method, with calcination between 250 and 700 °C is reported. The powder precursors were characterized by TG/DTA and high temperature X-ray diffraction (HTXRD). After heat treatment, the material was characterized by XRD and infrared spectroscopy. Ester and carbonate amounts were strictly related to Nd-doping. According to XRD patterns, the orthorhombic perovskite was obtained at 700 °C for SrSnO3 and SrSn0.99Nd0.01O3. For Sr0.99Nd0.01SnO3, the kinetics displayed an important hole in the crystallization process, as no peak was observed in HTXRD up to 700 °C, while a XRD patterns showed a crystalline material after calcination at 250 °C.

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Abstract  

Inorganic pigments containing lanthanides based on pseudo cubic structure of SrSnO3 have been prepared by solid state reaction between SrCO3, SnO2 and lanthanide oxides (Tb4O7, Pr6O11, CeO2) in the temperature range 1300–1550°C. The resultant materials were characterised by XRD, TG-DTA and colourimetric techniques were used. The most interesting colour properties were provided by SrTb0.4Sn0.6O3 prepared by firing at temperature 1500°C which has light yellow-green colour hue. The increase of temperature 1300–1500°C caused the creation of pigments with deeper and brighter colour hue. Colour properties of the samples prepared by calcination at 1550°C were of inferior quality due to structural changes from pseudo cubic to orthorhombic system.

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Journal of Thermal Analysis and Calorimetry
Authors: Vittorio Berbenni, Chiara Milanese, Giovanna Bruni, Alessandro Girella, and Amedeo Marini

-8842(00)00005-5 . 5. Azad , AM , Shyan , LLW , Pang , TY . 1999 . Synthesis, processing and microstructural characterization of CaSnO 3 and SrSnO 3 ceramics . J Alloys Compd . 282 : 109 – 124 10.1016/S0925

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