Artículos de revistas
Effect of the pH pre-adjustment on the formation of In(2)W(3)O(12 )and In6WO12 powders: Cluster coordination and optical band gap
Fecha
2020-01-01Registro en:
Boletin De La Sociedad Espanola De Ceramica Y Vidrio. Amsterdam: Elsevier, v. 59, n. 1, p. 2-14, 2020.
0366-3175
10.1016/j.bsecv.2019.02.001
WOS:000531475000002
Autor
Univ Fed Piaui
ICE Univ Fed Amazonas
Universidade Federal de São Carlos (UFSCar)
Universidade Estadual Paulista (Unesp)
Univ Estadual Piaui
Institución
Resumen
In this communication, diindium tristungstate (In2W3O12) and hexaindium tungstate (In6WO12) powders were synthesized by the co-precipitation method at different pH values and heat treatment at 1073 K for 2 h. X-ray diffraction patterns and Rietveld refinements were employed to analyze the long-range structural ordering as well as quantify the presence crystallographic phases, respectively. All powders obtained in pH ranging from 2 to 3.5 exhibited a mixture of In2W3O12 and gamma-tungsten oxide (gamma-WO3) phases. When prepared at pH close to 4, the powders presented both In2W3O12 and In6WO12 phases. All these crystalline structures were simulated in a three-dimensional visualization program by adopting the Rietveld refinements analysis as input data. The ultraviolet-visible spectra were employed to estimate the optical band gap energy of all powders for the first time. (C) 2019 Published by Elsevier Espana, S.L.U. on behalf of SECV.