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Title: Study of structural, electrical, and dielectric properties of phosphate-borate glasses and glass-ceramics

Abstract

In this work, phosphate-borate based glasses with molar composition 20.7P{sub 2}O{sub 5}–17.2Nb{sub 2}O{sub 5}–13.8WO{sub 3}–34.5A{sub 2}O–13.8B{sub 2}O{sub 3}, where A = Li, Na, and K, were prepared by the melt quenching technique. The as-prepared glasses were heat-treated in air at 800 °C for 4 h, which led to the formation of glass-ceramics. These high chemical and thermal stability glasses are good candidates for several applications such as fast ionic conductors, semiconductors, photonic materials, electrolytes, hermetic seals, rare-earth ion host solid lasers, and biomedical materials. The present work endorses the analysis of the electrical conductivity of the as-grown samples, and also the electrical, dielectric, and structural changes established by the heat-treatment process. The structure of the samples was analyzed using X-Ray powder Diffraction (XRD), Raman spectroscopy, and density measurements. Both XRD and Raman analysis confirmed crystals formation through the heat-treatment process. The electrical ac and dc conductivities, σ{sub ac} and σ{sub dc}, respectively, and impedance spectroscopy measurements as function of the temperature, varying from 200 to 380 K, were investigated for the as-grown and heat-treated samples. The impedance spectroscopy was measured in the frequency range of 100 Hz–1 MHz.

Authors:
; ; ;  [1]; ;  [2];  [3]
  1. Physics Department (I3N), Aveiro University, Campus Universitário de Santiago, Aveiro (Portugal)
  2. Mechanics Engineering Department, Ceará Federal University, Fortaleza (Brazil)
  3. Equipe Physico-Chimie la Matière Condensée, Faculté des Sciences de Meknès, Meknès (Morocco)
Publication Date:
OSTI Identifier:
22597831
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:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; BORATES; CERAMICS; CRYSTALS; DENSITY; DIELECTRIC MATERIALS; DIELECTRIC PROPERTIES; ELECTRIC CONDUCTIVITY; ELECTRIC CONDUCTORS; ELECTROLYTES; GLASS; HEAT; HEAT TREATMENTS; IMPEDANCE; MHZ RANGE 01-100; PHOSPHATES; RAMAN SPECTROSCOPY; RARE EARTHS; SEMICONDUCTOR MATERIALS; X RADIATION; X-RAY DIFFRACTION

Citation Formats

Melo, B. M. G., Graça, M. P. F., E-mail: mpfg@ua.pt, Prezas, P. R., Valente, M. A., Almeida, A. F., Freire, F. N. A., and Bih, L. Study of structural, electrical, and dielectric properties of phosphate-borate glasses and glass-ceramics. United States: N. p., 2016. Web. doi:10.1063/1.4958935.
Melo, B. M. G., Graça, M. P. F., E-mail: mpfg@ua.pt, Prezas, P. R., Valente, M. A., Almeida, A. F., Freire, F. N. A., & Bih, L. Study of structural, electrical, and dielectric properties of phosphate-borate glasses and glass-ceramics. United States. doi:10.1063/1.4958935.
Melo, B. M. G., Graça, M. P. F., E-mail: mpfg@ua.pt, Prezas, P. R., Valente, M. A., Almeida, A. F., Freire, F. N. A., and Bih, L. Sun . "Study of structural, electrical, and dielectric properties of phosphate-borate glasses and glass-ceramics". United States. doi:10.1063/1.4958935.
@article{osti_22597831,
title = {Study of structural, electrical, and dielectric properties of phosphate-borate glasses and glass-ceramics},
author = {Melo, B. M. G. and Graça, M. P. F., E-mail: mpfg@ua.pt and Prezas, P. R. and Valente, M. A. and Almeida, A. F. and Freire, F. N. A. and Bih, L.},
abstractNote = {In this work, phosphate-borate based glasses with molar composition 20.7P{sub 2}O{sub 5}–17.2Nb{sub 2}O{sub 5}–13.8WO{sub 3}–34.5A{sub 2}O–13.8B{sub 2}O{sub 3}, where A = Li, Na, and K, were prepared by the melt quenching technique. The as-prepared glasses were heat-treated in air at 800 °C for 4 h, which led to the formation of glass-ceramics. These high chemical and thermal stability glasses are good candidates for several applications such as fast ionic conductors, semiconductors, photonic materials, electrolytes, hermetic seals, rare-earth ion host solid lasers, and biomedical materials. The present work endorses the analysis of the electrical conductivity of the as-grown samples, and also the electrical, dielectric, and structural changes established by the heat-treatment process. The structure of the samples was analyzed using X-Ray powder Diffraction (XRD), Raman spectroscopy, and density measurements. Both XRD and Raman analysis confirmed crystals formation through the heat-treatment process. The electrical ac and dc conductivities, σ{sub ac} and σ{sub dc}, respectively, and impedance spectroscopy measurements as function of the temperature, varying from 200 to 380 K, were investigated for the as-grown and heat-treated samples. The impedance spectroscopy was measured in the frequency range of 100 Hz–1 MHz.},
doi = {10.1063/1.4958935},
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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