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Title: Influence of Cu-doping on the structural and optical properties of CaTiO{sub 3} powders

Abstract

Highlights: • Ca{sub 1−x}Cu{sub x}TiO{sub 3} powders were successfully synthesized via a polymeric precursor method. • Effects of Cu incorporated on the Ca-site into the CaTiO{sub 3} lattice as host matrix has been investigated. • The optical behavior reveals that the Ca{sub 1−x}Cu{sub x}TiO{sub 3} powders have potential applications in emerging technologies. - Abstract: Here, we report on the effect of chemical substitution on the structural and optical properties of Cu-doped CaTiO{sub 3} (CTO) polycrystalline powders synthesized by the polymeric precursor method. Our findings are discussed based on the structural order-disorder effects originating from the modification of the Ca{sub 1−x}Cu{sub x}TiO{sub 3} microcrystal matrix. These results may elucidate the compositional modulation and methods of controlling the structural design, as well as reveal the changes in the optical behavior of this system at an atomic level.

Authors:
;  [1];  [2];  [3]; ;  [1];  [3]; ;  [1]
  1. UNESP-Universidade Estadual Paulista, P.O. Box 355, 14801-907, Araraquara, SP (Brazil)
  2. Department of Chemistry, Federal Technological University of Parana (UTFPR), PO Box 3131, 86036-370, Londrina/PR (Brazil)
  3. DQ-UFSCar-Universidade Federal de São Carlos, P.O. Box 676, 13565-905, São Carlos, SP (Brazil)
Publication Date:
OSTI Identifier:
22581613
Resource Type:
Journal Article
Resource Relation:
Journal Name: Materials Research Bulletin; Journal Volume: 81; Other Information: Copyright (c) 2016 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:
36 MATERIALS SCIENCE; CALCIUM COMPOUNDS; CERAMICS; CONCENTRATION RATIO; DOPED MATERIALS; MATRIX MATERIALS; MICROSTRUCTURE; OPTICAL PROPERTIES; ORDER-DISORDER TRANSFORMATIONS; POLYCRYSTALS; POWDERS; SYNTHESIS; TITANATES

Citation Formats

Oliveira, L.H., Moura, A.P. de, La Porta, F.A., E-mail: felipe_laporta@yahoo.com.br, Nogueira, I.C., Aguiar, E.C., Sequinel, T., Rosa, I.L.V., Longo, E., and Varela, J.A.. Influence of Cu-doping on the structural and optical properties of CaTiO{sub 3} powders. United States: N. p., 2016. Web. doi:10.1016/J.MATERRESBULL.2016.04.024.
Oliveira, L.H., Moura, A.P. de, La Porta, F.A., E-mail: felipe_laporta@yahoo.com.br, Nogueira, I.C., Aguiar, E.C., Sequinel, T., Rosa, I.L.V., Longo, E., & Varela, J.A.. Influence of Cu-doping on the structural and optical properties of CaTiO{sub 3} powders. United States. doi:10.1016/J.MATERRESBULL.2016.04.024.
Oliveira, L.H., Moura, A.P. de, La Porta, F.A., E-mail: felipe_laporta@yahoo.com.br, Nogueira, I.C., Aguiar, E.C., Sequinel, T., Rosa, I.L.V., Longo, E., and Varela, J.A.. Thu . "Influence of Cu-doping on the structural and optical properties of CaTiO{sub 3} powders". United States. doi:10.1016/J.MATERRESBULL.2016.04.024.
@article{osti_22581613,
title = {Influence of Cu-doping on the structural and optical properties of CaTiO{sub 3} powders},
author = {Oliveira, L.H. and Moura, A.P. de and La Porta, F.A., E-mail: felipe_laporta@yahoo.com.br and Nogueira, I.C. and Aguiar, E.C. and Sequinel, T. and Rosa, I.L.V. and Longo, E. and Varela, J.A.},
abstractNote = {Highlights: • Ca{sub 1−x}Cu{sub x}TiO{sub 3} powders were successfully synthesized via a polymeric precursor method. • Effects of Cu incorporated on the Ca-site into the CaTiO{sub 3} lattice as host matrix has been investigated. • The optical behavior reveals that the Ca{sub 1−x}Cu{sub x}TiO{sub 3} powders have potential applications in emerging technologies. - Abstract: Here, we report on the effect of chemical substitution on the structural and optical properties of Cu-doped CaTiO{sub 3} (CTO) polycrystalline powders synthesized by the polymeric precursor method. Our findings are discussed based on the structural order-disorder effects originating from the modification of the Ca{sub 1−x}Cu{sub x}TiO{sub 3} microcrystal matrix. These results may elucidate the compositional modulation and methods of controlling the structural design, as well as reveal the changes in the optical behavior of this system at an atomic level.},
doi = {10.1016/J.MATERRESBULL.2016.04.024},
journal = {Materials Research Bulletin},
number = ,
volume = 81,
place = {United States},
year = {Thu Sep 15 00:00:00 EDT 2016},
month = {Thu Sep 15 00:00:00 EDT 2016}
}
  • Structures of compounds in the Cu{sub 2}Se-In{sub 2}Se{sub 3}-Ga{sub 2}Se{sub 3} system have been investigated through X-ray diffraction. Single crystal structure studies for the so-called stoichiometric compounds Cu(In,Ga)Se{sub 2} (CIGSe) confirm that the chalcopyrite structure (space group I4-bar 2d) is very flexible and can adapt itself to the substitution of Ga for In. On the other hand a structure modification is evidenced in the Cu{sub 1-z}(In{sub 0.5}Ga{sub 0.5}){sub 1+z/3}Se{sub 2} series when the copper vacancy ratio (z) increases; the chalcopyrite structure turns to a modified-stannite structure (I4-bar 2m) when z{>=}0.26. There is a continuous evolution of the structure from Cu{submore » 0.74}(In{sub 0.5}Ga{sub 0.5}){sub 1.09}Se{sub 2} to Cu{sub 0.25}(In{sub 0.5}Ga{sub 0.5}){sub 1.25}Se{sub 2} ((i.e. Cu(In{sub 0.5}Ga{sub 0.5}){sub 5}Se{sub 8}), including Cu{sub 0.4}(In{sub 0.5}Ga{sub 0.5}){sub 1.2}Se{sub 2} (i.e. Cu(In{sub 0.5}Ga{sub 0.5}){sub 3}Se{sub 5}). From this single crystal structural investigation, it is definitively clear that no ordered vacancy compound exists in that series. X-ray photoemission spectroscopy study shows for the first time that the surface of powdered Cu{sub 1-z}(In{sub 0.5}Ga{sub 0.5}){sub 1+z/3}Se{sub 2} compounds (z{ne}0) is more copper-poor than the bulk. The same result has often been observed on CIGSe thin films material for photovoltaic applications. In addition, optical band gaps of these non-stoichiometric compounds increase from 1.2 to 1.4 eV when z varies from 0 to 0.75. - Abstract: Pseudo-ternary diagram in the Cu{sub 2}Se-In{sub 2}Se{sub 3}-Ga{sub 2}Se{sub 3} system showing the composition of all the synthesized compounds. The crystal structure of the compounds corresponding to red circles are presented in this study.« less
  • The present work report a series of trivalent Europium (Eu{sup 3+}) doped well crystallized perovskite CaTiO{sub 3} phosphors successfully synthesized by chemical co-precipitation method. The crystal structure was confirmed by X-ray diffraction (XRD) which is in good agreement with pure orthorhombic phase with space group Pbnm, and it also indicated that the incorporation of the dopant did not affect the crystal structure. The impact of doping on the photoluminescence performances of the sample has been investigated by emission, excitation, and diffuse reflectance spectra at the room temperature. Photoluminescence spectra of Eu{sup 3+} doped CaTiO{sub 3} nanophosphor revealed the characteristic emissionmore » peak around wavelength 618 nm in the visible region upon the excitation of near-UV light at wavelength 397 nm due to {sup 5}D{sub 0} → {sup 7}F{sub 2} transition in Eu{sup 3+}. It was further proved that the dipole– dipole interactions results in the concentration quenching of Eu{sup 3+} in CaTiO{sub 3}:Eu{sup 3+} nanophosphors. The elemental composition of sample carried out by energy dispersive spectroscopy (EDS). EDS analysis reveals that the Eu{sup 3+} doped successfully into host CaTiO{sub 3}. The experimental result reveals that prepared nanophosphor can be used in the application of solid state lighting devices.« less
  • In this paper, Mn substituted at Cu site in YBa[sub 2]Cu[sub 3[minus] x]Mn[sub x]O[sub y] (x = 0.0, 0.03, 0.09, 0.15, 0.21, 0.30) system has been studied. It is discussed that the resistivity upturn at low temperature in heavily doped samples may be due to the presence of Mn derived impurity phase. Mn appeared to reduce hole density without affecting the 1/T behavior of the Hall coefficient (R[sub H]). An attempt has been made to correlate the results of susceptibility with resistivity, hole density and structural changes with the Mn content.
  • The stability of the A/sub n/B/sub n/O/sub 3n+2/ phases, whose structure is derived from the perovskite structure, was investigated through x-ray diffraction, in the following systems: La/sub 2/Ti/sub 2/O/sub 7/--CaTiO/sub 3/, Nd/sub 2/Ti/sub 2/O/sub 7/--CaTiO/sub 3/ and Ca/sub 2/Nb/sub 2/O/sub 7/--CaTiO/sub 3/. Some of the phases quenched from the liquid are metastable and include vacancies over A and B sites. A model of formation of these phases is proposed.
  • Structural and dielectric properties of polycrystalline YMnO{sub 3} (x = 0.0, 0.10 and 0.20) which was prepared by solid-state reaction route, have been investigated. The X-ray diffraction pattern reveals that all the samples are in single phase and show hexagonal structure with P63cm space group. The particle size decreases with increase in Sm doping while to that X-ray density increases with increasing x. The dielectric constant (ε’) of Y{sub 1-x}Sm{sub x}MnO{sub 3} measured in the frequency range 10 Hz to 1MHz is much higher at lower frequencies (≤ 1KHz) and its value decreases with enhanced frequency. At very high frequencies, ε’more » becomes frequency independent and is attributed to Maxwell Wagner type of interfacial polarization model. A very high value of dielectric constant ∼18642 is observed for x = 10%. The dielectric loss (tan δ) decreases wit increase in Sm doping.« less