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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.)

Experimental and theoretical study to explain the morphology of CaMoO4 crystals

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Oliveira, F. K. F. [1] ; Oliveira, M. C. [2] ; Gracia, L. [3] ; Tranquilin, R. L. [1] ; Paskocimas, C. A. [1] ; Motta, F. V. [1] ; Longo, E. [4] ; Andres, J. [2] ; Bomio, M. R. D. [1]
Total Authors: 9
[1] Univ Fed Rio Grande Do Norte UFRN, DEMat, LSQM, POB 1524, BR-59078970 Natal, RN - Brazil
[2] Univ Jaume 1, Dept Quim Fis & Analit, Castellon de La Plana 12071 - Spain
[3] Univ Valencia, Dept Phys Chem, E-46100 Burjassot - Spain
[4] Univ Fed Sao Carlos, CDMF, UFSCar, POB 676, Sao Carlos, SP - Brazil
Total Affiliations: 4
Document type: Journal article
Source: JOURNAL OF PHYSICS AND CHEMISTRY OF SOLIDS; v. 114, p. 141-152, MAR 2018.
Web of Science Citations: 3

CaMoO4 crystals were prepared by a controlled co-precipitation method and processed in a domestic microwave assisted hydrothermal system with two different surfactants (ethyl 4-dimethylaminobenzoate and 1,2,4,5-benzenetetracarboxylic dianhydride). The corresponding structures were characterized by X-ray diffraction and Rietveld refinement techniques, Fourier transform infrared spectroscopy, ultraviolet visible absorption spectroscopy, and photoluminescence measurements. Field emission scanning electron microscopy was used to investigate the morphology of the as-synthesized aggregates. The structure, the surface stability of the (001), (112), (100), (110), (101), and (111) surfaces of CaMoO4, and their morphological transformations were investigated through systematic first-principles calculations within the density functional theory method at the B3LYP level. Analysis of the surface structures showed that the electronic properties were associated with the presence of undercoordinated{[}CaO]x (x = 5 and 6) and {[}MoOy] (y = 4 and 3) clusters. The relative surfaces energies were tuned to predict a complete map of the morphologies available through a Wulff construction approach. The results reveal that the experimental and theoretical morphologies obtained coincide when the surface energies of the (001) and (101) surfaces increase, while the surface energy of the (100) facet decreases simultaneously. The results provide a comprehensive catalog of the morphologies most likely to be present under realistic conditions, and will serve as a starting point for future studies on the surface chemistry of CaMoO4] crystals. (AU)

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