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(Reference retrieved automatically from Web of Science through information on FAPESP grant and its corresponding number as mentioned in the publication by the authors.)

Synthesis and characterization of metastable beta-Ag2WO4: an experimental and theoretical approach

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Lemos, Pablo S. [1] ; Altomare, A. [2] ; Gouveia, A. F. [1] ; Nogueira, I. C. [3] ; Gracia, L. [4, 5] ; Llusar, R. [5] ; Andres, J. [5] ; Longo, E. [4, 1] ; Cavalcante, Laecio S. [6]
Total Authors: 9
[1] Univ Fed Sao Carlos, DQ, BR-13565905 Sao Paulo - Brazil
[2] CNR, Inst Crystallog, I-70126 Bari - Italy
[3] PPG Engn Mat, Inst Fed Maranhao, BR-65030005 Sao Luis, MA - Brazil
[4] Univ Estadual Paulista, CDMF, BR-14801907 Araraquara, SP - Brazil
[5] Univ Jaume 1, Dept Analyt & Phys Chem, Castellon de La Plana 12071 - Spain
[6] Univ Estadual Piaui, GERATEC, DQ, BR-64002150 Teresina, PI - Brazil
Total Affiliations: 6
Document type: Journal article
Source: DALTON TRANSACTIONS; v. 45, n. 3, p. 1185-1191, 2016.
Web of Science Citations: 8

Metastable silver tungstate (beta-Ag2WO4) has attracted much attention lately because of its many potential applications. However, the synthesis of metastable phases of inorganic compounds is challenging because of the ease of transformation to the stable phase. We have overcome this challenge and have successfully synthesized beta-Ag2WO4 microcrystals using a dropwise precipitation (DP) method in aqueous media at low temperature. The microcrystals were characterized by X-ray diffraction (XRD), including powder X-ray diffraction structural determination, field-emission scanning electron microscopy (FE-SEM), and micro-Raman/ultraviolet-visible (UV-vis) diffuse reflectance spectroscopy. To complement the experimental data, we present first-principles quantum-mechanical density functional theory (DFT) calculations. Using XRD data, Raman/UV-vis data, and the determined optical band gap, together with geometric optimization calculations, we confirmed the structure of this compound. beta-Ag2WO4 has a hexagonal structure with a P6(3)/m space group. The building blocks of the lattice comprise two types of W-O clusters, {[}WO4] and {[}WO5], coordinated to four and five O atoms, respectively, and two types of Ag-O clusters, {[}AgO6], and {[}AgO5], linked to six and five O atoms, respectively. This type of fundamental study, combining multiple experimental methods and first-principles calculations, helps to obtain a basic understanding of the local structure and bonding in the material. (AU)

FAPESP's process: 13/26671-9 - Theoretical and experimental study of multifunctional semiconductors
Grantee:Amanda Fernandes Gouveia
Support type: Scholarships in Brazil - 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