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Title: Photoluminescent BaMoO{sub 4} nanopowders prepared by complex polymerization method (CPM)

Abstract

The BaMoO{sub 4} nanopowders were prepared by the Complex Polymerization Method (CPM). The structure properties of the BaMoO{sub 4} powders were characterized by FTIR transmittance spectra, X-ray diffraction (XRD), Raman spectra, photoluminescence spectra (PL) and high-resolution scanning electron microscopy (HR-SEM). The XRD, FTIR and Raman data showed that BaMoO{sub 4} at 300 deg. C was disordered. At 400 deg. C and higher temperature, BaMoO{sub 4} crystalline scheelite-type phases could be identified, without the presence of additional phases, according to the XRD, FTIR and Raman data. The calculated average crystallite sizes, calculated by XRD, around 40 nm, showed the tendency to increase with the temperature. The crystallite sizes, obtained by HR-SEM, were around of 40-50 nm. The sample that presented the highest intensity of the red emission band was the one heat treated at 400 deg. C for 2 h, and the sample that displayed the highest intensity of the green emission band was the one heat treated at 700 deg. C for 2 h. The CPM was shown to be a low cost route for the production of BaMoO{sub 4} nanopowders, with the advantages of lower temperature, smaller time and reduced cost. The optical properties observed for BaMoO{sub 4} nanopowdersmore » suggested that this material is a highly promising candidate for photoluminescent applications.« less

Authors:
 [1];  [2];  [3];  [4];  [4];  [5];  [6]
  1. Laboratorio de Analise Termica e Materiais, Departamento de Quimica, Universidade Federal do Rio Grande do Norte, 59072-970 Natal, RN (Brazil). E-mail: apamarques@liec.ufscar.br
  2. Laboratorio de Analise Termica e Materiais, Departamento de Quimica, Universidade Federal do Rio Grande do Norte, 59072-970 Natal, RN (Brazil)
  3. Departamento de Engenharia Mecanica, Universidade Federal do Rio Grande do Norte, 59072-970 Natal, RN (Brazil)
  4. Laboratorio de Semicondutores, Departamento de Fisica, Universidade Federal de Sao Carlos, 13565-905 Sao Carlos, SP (Brazil)
  5. Laboratorio Interdisciplinar de Eletroquimica e Ceramica, CMDMC, Departamento de Quimica, Universidade Federal de Sao Carlos 13565-905, Sao Carlos, SP (Brazil)
  6. CMDMC, LIEC, Instituto de Quimica, Universidade Estadual Paulista, 14801-907 Araraquara, SP (Brazil)
Publication Date:
OSTI Identifier:
20784908
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Solid State Chemistry; Journal Volume: 179; Journal Issue: 3; Other Information: DOI: 10.1016/j.jssc.2005.11.020; PII: S0022-4596(05)00561-X; Copyright (c) 2005 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; BARIUM COMPOUNDS; FOURIER TRANSFORMATION; HEAT TREATMENTS; INFRARED SPECTRA; MOLYBDATES; OPTICAL PROPERTIES; PHOTOLUMINESCENCE; POLYMERIZATION; POWDERS; RAMAN SPECTRA; SCANNING ELECTRON MICROSCOPY; X-RAY DIFFRACTION

Citation Formats

Azevedo Marques, Ana Paula de, Melo, Dulce M.A. de, Paskocimas, Carlos A., Pizani, Paulo S., Joya, Miryam R., Leite, Edson R., and Longo, Elson. Photoluminescent BaMoO{sub 4} nanopowders prepared by complex polymerization method (CPM). United States: N. p., 2006. Web. doi:10.1016/j.jssc.2005.11.020.
Azevedo Marques, Ana Paula de, Melo, Dulce M.A. de, Paskocimas, Carlos A., Pizani, Paulo S., Joya, Miryam R., Leite, Edson R., & Longo, Elson. Photoluminescent BaMoO{sub 4} nanopowders prepared by complex polymerization method (CPM). United States. doi:10.1016/j.jssc.2005.11.020.
Azevedo Marques, Ana Paula de, Melo, Dulce M.A. de, Paskocimas, Carlos A., Pizani, Paulo S., Joya, Miryam R., Leite, Edson R., and Longo, Elson. Wed . "Photoluminescent BaMoO{sub 4} nanopowders prepared by complex polymerization method (CPM)". United States. doi:10.1016/j.jssc.2005.11.020.
@article{osti_20784908,
title = {Photoluminescent BaMoO{sub 4} nanopowders prepared by complex polymerization method (CPM)},
author = {Azevedo Marques, Ana Paula de and Melo, Dulce M.A. de and Paskocimas, Carlos A. and Pizani, Paulo S. and Joya, Miryam R. and Leite, Edson R. and Longo, Elson},
abstractNote = {The BaMoO{sub 4} nanopowders were prepared by the Complex Polymerization Method (CPM). The structure properties of the BaMoO{sub 4} powders were characterized by FTIR transmittance spectra, X-ray diffraction (XRD), Raman spectra, photoluminescence spectra (PL) and high-resolution scanning electron microscopy (HR-SEM). The XRD, FTIR and Raman data showed that BaMoO{sub 4} at 300 deg. C was disordered. At 400 deg. C and higher temperature, BaMoO{sub 4} crystalline scheelite-type phases could be identified, without the presence of additional phases, according to the XRD, FTIR and Raman data. The calculated average crystallite sizes, calculated by XRD, around 40 nm, showed the tendency to increase with the temperature. The crystallite sizes, obtained by HR-SEM, were around of 40-50 nm. The sample that presented the highest intensity of the red emission band was the one heat treated at 400 deg. C for 2 h, and the sample that displayed the highest intensity of the green emission band was the one heat treated at 700 deg. C for 2 h. The CPM was shown to be a low cost route for the production of BaMoO{sub 4} nanopowders, with the advantages of lower temperature, smaller time and reduced cost. The optical properties observed for BaMoO{sub 4} nanopowders suggested that this material is a highly promising candidate for photoluminescent applications.},
doi = {10.1016/j.jssc.2005.11.020},
journal = {Journal of Solid State Chemistry},
number = 3,
volume = 179,
place = {United States},
year = {Wed Mar 15 00:00:00 EST 2006},
month = {Wed Mar 15 00:00:00 EST 2006}
}
  • Highlights: • SrSi{sub 2}O{sub 2}N{sub 2}: Eu{sup 2+} phosphor was prepared by polymer metal complex (pechini method). • The annealing time was decreased from 6 h in solid state method to 3 h. • The particles are crystalline and dispersed well with average size 6.5 μm. - Abstract: Green emitting Sr{sub (1−x)}Si{sub 2}O{sub 2}N{sub 2}: xEu{sup 2+} (x = 0, 0.02, 0.04, 0.06, 0.08 and 0.1) phosphors were synthesized by polymer metal complex or pechini method. The XRD results confirm the formation of a pure phase at 1400 °C for 3 h. The SEM and particles size results indicate thatmore » the prepared phosphor consists of a polyhedral crystalline shape with well dispersed and the average particle size around 6.5 μm. The maximum PL intensity was found at 0.04% Eu{sup 2+} with a wide emission band between 460 and 640 nm and a green emission peak at 531.4 nm. The external quantum efficiency of 0.04% Eu{sup 2+} sample was 43.13%. The results indicate that pechini method is an alternative way and close in efficiency to the solid state method to prepare SrSi{sub 2}O{sub 2}N{sub 2} phosphor with higher homogeneity and more uniform size distribution for near UV and blue region applications for white light emitting diodes WLEDs.« less
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