Monodisperse Ba_0.6Sr_0.4TiO₃ hollow spheres via a modified template-assisted method

Monodisperse Ba_0.6Sr_0.4TiO₃ hollow spheres (HS-BST) with good spherical morphology, uniform size and accurate proportion of Ba/Sr were systhesised using a novel template-assisted method. The particle size and shell thickness of HS-BST particles were adjusted by controlling synthesis conditions, including carbon sphere size, reactant concentrations, reaction time and temperature, as well as the content of hydrolytic inhibitor. The surface morphology of HS-BST could be improved by the addition of appropriate hydrolytic inhibitor (triethanolamine, TEA), as it could reasonably control the diffusion of metal ions and prevent problems such as BST coating uniformity caused by improper hydrolysis rates. The accurate proportion of Ba/Sr was obtained with the presence of hydrolytic inhibitor. The facile synthetic approach would provide a new insight into the design and fabrication of hollow spheres of other perovskite oxides.