Study of surfaces and morphologies of proteic sol-gel derived barium aluminate nanopowders: An experimental and computational study

BaAl2O4 nanoparticles samples were prepared by sol gel proteic route. The preparation of the precursor mixture and the formation of the ceramic product were monitored using TG/DTA, X-ray diffraction (XRD), electron microscopy (SEM, TEM). The results show that sol gel proteic route is a reliable method for the synthesis of pure BaAl2O4 powders and that irregular hexagonal facetted nanoparticles are observed. Atomistic modeling was used to calculate the structures and energies of 24 (hkl) surfaces and to evaluate morphologies of BaAl2O4 at the thermodynamic and pseudo-kinetic equilibrium. The calculations show that the two most stable surfaces are the (001) and (011) with a surface energy of 133 J m(-2) and 136 J m(-2) respectively and that the predicted morphologies are in accord with experiment. (C) 2012 Elsevier B.V. All rights reserved.