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Title: Structural, optical, and electrical properties of SmNbO{sub 4}

Abstract

Rare-earth orthoniobates constitute a class of materials that has been exploited due to their interesting physical properties depending on the lanthanide element. Besides paramagnetism, ferroelasticity, and negative compressibility, these materials are known by their interesting optical properties and mixed types of conduction processes (protonic, ionic, and electronic). In this work, two types of SmNbO{sub 4} samples were studied: polycrystalline samples, prepared by a sol-gel route using the Pechini method, and single crystalline fibres grown by the Laser Floating Zone technique. These samples were structurally characterized based on powder and single-crystal X-ray diffraction studies. A metastable tetragonal phase, stabilized by grain size, was identified in the synthesized powders. After a sintering process of such powders, a single monoclinic phase was obtained. Complementarily, scanning electron microscopy and Raman spectroscopy analyses were performed to these samples. Photoluminescence and photoluminescence excitation spectroscopic studies allowed identifying more than one optically active centre of the trivalent samarium ion in the analysed material. Impedance spectroscopy measurements have shown a large variation of the ac conductivity as a function of temperature, assigned to a protonic conduction and to native ionic conduction mechanisms.

Authors:
; ; ; ;  [1]
  1. I3N Department of Physics, University of Aveiro, Campus Universitário de Santiago, 3810-193 Aveiro (Portugal)
Publication Date:
OSTI Identifier:
22597795
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 120; Journal Issue: 5; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; COMPRESSIBILITY; ELECTRICAL PROPERTIES; GRAIN SIZE; IMPEDANCE; MONOCLINIC LATTICES; MONOCRYSTALS; OPTICAL PROPERTIES; PARAMAGNETISM; PHOTOLUMINESCENCE; POLYCRYSTALS; POWDERS; RAMAN SPECTROSCOPY; SAMARIUM IONS; SAMARIUM OXIDES; SCANNING ELECTRON MICROSCOPY; SINTERING; SOL-GEL PROCESS; TEMPERATURE DEPENDENCE; X-RAY DIFFRACTION; ZONE MELTING

Citation Formats

Nico, C., E-mail: claudionico@ua.pt, Soares, M. R. N., Costa, F. M., Monteiro, T., and Graça, M. P. F.. Structural, optical, and electrical properties of SmNbO{sub 4}. United States: N. p., 2016. Web. doi:10.1063/1.4958953.
Nico, C., E-mail: claudionico@ua.pt, Soares, M. R. N., Costa, F. M., Monteiro, T., & Graça, M. P. F.. Structural, optical, and electrical properties of SmNbO{sub 4}. United States. doi:10.1063/1.4958953.
Nico, C., E-mail: claudionico@ua.pt, Soares, M. R. N., Costa, F. M., Monteiro, T., and Graça, M. P. F.. Sun . "Structural, optical, and electrical properties of SmNbO{sub 4}". United States. doi:10.1063/1.4958953.
@article{osti_22597795,
title = {Structural, optical, and electrical properties of SmNbO{sub 4}},
author = {Nico, C., E-mail: claudionico@ua.pt and Soares, M. R. N. and Costa, F. M. and Monteiro, T. and Graça, M. P. F.},
abstractNote = {Rare-earth orthoniobates constitute a class of materials that has been exploited due to their interesting physical properties depending on the lanthanide element. Besides paramagnetism, ferroelasticity, and negative compressibility, these materials are known by their interesting optical properties and mixed types of conduction processes (protonic, ionic, and electronic). In this work, two types of SmNbO{sub 4} samples were studied: polycrystalline samples, prepared by a sol-gel route using the Pechini method, and single crystalline fibres grown by the Laser Floating Zone technique. These samples were structurally characterized based on powder and single-crystal X-ray diffraction studies. A metastable tetragonal phase, stabilized by grain size, was identified in the synthesized powders. After a sintering process of such powders, a single monoclinic phase was obtained. Complementarily, scanning electron microscopy and Raman spectroscopy analyses were performed to these samples. Photoluminescence and photoluminescence excitation spectroscopic studies allowed identifying more than one optically active centre of the trivalent samarium ion in the analysed material. Impedance spectroscopy measurements have shown a large variation of the ac conductivity as a function of temperature, assigned to a protonic conduction and to native ionic conduction mechanisms.},
doi = {10.1063/1.4958953},
journal = {Journal of Applied Physics},
number = 5,
volume = 120,
place = {United States},
year = {Sun Aug 07 00:00:00 EDT 2016},
month = {Sun Aug 07 00:00:00 EDT 2016}
}
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