Cr(III) and Eu(III) as doping ions in the Zn7Sb2O12 semiconductor: investigation o...
| Full text | |
| Author(s): |
Almeida, M. A. P.
[1]
;
Lima, J. R. O.
[1]
;
Morila-Santos, C.
[2]
;
Lisboa Filho, P. N.
[3]
;
Siu Li, M.
[4]
;
Longo, E.
[5]
;
Cavalcante, L. S.
[6]
Total Authors: 7
|
| Affiliation: | [1] Univ Fed Maranhao, Coordenacao Ciencias & Tecnol, BR-65080805 Sao Luis, MA - Brazil
[2] Univ Fed Ceara, Dept Fis, BR-60455760 Fortaleza, Ceara - Brazil
[3] UNESP Univ Estadual Paulista, MAv DF, BR-17033360 Bauru, SP - Brazil
[4] Univ Sao Paulo, Inst Fis Sao Carlos, BR-13560970 Sao Carlos, SP - Brazil
[5] UNESP Univ Estadual Paulista, Inst Quim, BR-14800900 Araraquara, SP - Brazil
[6] Univ Estadual Piaui, CCN DQ GERATEC, BR-64002150 Teresina, PI - Brazil
Total Affiliations: 6
|
| Document type: | Journal article |
| Source: | Journal of Sol-Gel Science and Technology; v. 72, n. 3, p. 648-654, DEC 2014. |
| Web of Science Citations: | 1 |
| Abstract | |
The effect of zinc ions (Zn2+) on the structure, morphology and optical properties of (Ca1-x Zn (x) )WO4 microcrystals with (x = 0, 0.01, 0.02, and 0.03) obtained by the microwave-hydrothermal method at 170 A degrees C for 1 h is reported in this letter. These microcrystals were characterized by X-ray diffraction (XRD), Rietveld refinement, energy dispersive X-rays spectroscopy (EDXS) and field emission scanning electron microscopy (FE-SEM) images. The optical properties were investigated by ultraviolet-visible (UV-Vis) diffuse reflectance spectroscopy and photoluminescence (PL) measurements. XRD patterns and Rietveld refinement data indicated that all the (Ca1-x Zn (x) )WO4 microcrystals present a tetragonal structure and a reduction of lattice parameters and unit cell volume occurs with the increase of Zn2+. EDXS data confirms that the elemental chemical composition was achieved for (Ca1-x Zn (x) )WO4 microcrystals. FE-SEM images showed that the replacement of Ca2+ by the Zn2+ promotes a reduction of average crystals size and considerable changes in crystal shape starting from dumbbell-like to decorative ball-like (Ca1-x Zn (x) )WO4 microcrystals. UV-Vis spectra evidenced a small increase in optical band gap values (from 5.72 to 5.76 eV). Finally, PL emission of (Ca1-x Zn (x) )WO4 microcrystals was improved until x = 0.02 due to the presence of defects at medium range and new intermediate electronic levels in the band gap associated to the Zn2+ content. (AU) | |
| FAPESP's process: | 12/18597-0 - Investigation of photoluminescent, photocatalytic and bactericides proprieties of (Ca1-xZnx)WO4 and (Ca1-xAg2x)WO4 |
| Grantee: | Marcio Aurelio Pinheiro Almeida |
| Support type: | Scholarships in Brazil - Post-Doctorate |
| FAPESP's process: | 09/50303-4 - Optical and photocatalytic properties of ZnMoO4 and ZnWO4 |
| Grantee: | Laécio Santos Cavalcante |
| Support type: | Scholarships in Brazil - Post-Doctorate |
| FAPESP's process: | 13/07296-2 - CDMF - Center for the Development of Functional Materials |
| Grantee: | Elson Longo da Silva |
| Support type: | Research Grants - Research, Innovation and Dissemination Centers - RIDC |