Synthesis and morphological transformation of BaWO4 crystals: Experimental and theoretical insights

Abstract: BaWO4 crystals have been obtained by a co-precipitation method, and their structures were characterized by X-ray diffraction and Rietveld refinement techniques, while field emission scanning electron microscopy was utilized to investigate the morphology of the as-synthesized aggregates. Geometries, bulk electronic properties, surface energies, and surface tension of the obtained BaWO4 crystals were evaluated using first-principles quantum mechanical calculations. A theoretical model based on the Wulff construction was introduced to explain possible crystal morphologies by tuning their surface chemistry, which is related to the relative stability of the faceted crystals. Both the experimental and theoretical data revealed the presence of (112), (001), and (100) facets with low values of surface energy in the BaWO4 crystals. The experimental morphologies of the as-synthesized samples are similar to the theoretically obtained shapes when surface energy values for the (001) and (100) surfaces are increased simultaneously. (C) 2016 Elsevier Ltd and Techna Group S.r.l. All rights reserved.

Author(s): Oliveira, MC; Gracia, L; Nogueira, IC; Gurgel, MFD; Mercury, JMR; Longo, E; Andres, J.

CERAMICS INTERNATIONAL

DOI: 10.1016/j.ceramint.2016.03.225