Regensburg 2019 – wissenschaftliches Programm
CPP 25.13: Poster
Dienstag, 2. April 2019, 14:00–16:00, Poster B1
Synthesis of Well-Controlled Titania Hollow Spheres — •Anna Lechner and Markus Retsch — University of Bayreuth, Bayreuth, Germany
Over the past few decades, the interest in titania based materials increased enormously because of its strong oxidative potential and photocatalytic activity.
The controlled synthesis of monodisperse and well-defined titania particles on the mesoscale still poses a challenge. In particular core-shell architectures and hollow spheres are interesting titania morphologies owing to their hierarchical architecture controlled by a large diameter and thin shell. In contrast to the synthesis of silica hollow spheres, the synthesis of titania hollow spheres is more challenging because of the highly reactive precursors.
This contribution presents the three steps of a controlled and scalable synthesis of titania hollow spheres of various sizes. First, the synthesis of polystyrene particles via dispersion polymerization is explained. Here, several parameters for the adjustment of the particle size are discussed. Furthermore, the synthesis of smooth titania shells of defined thicknesses is presented following a simple precursor condensation strategy. Finally, the template core removal can compromise the integrity of the titania shell. We assess strategies to retain the structural control to yield monodisperse titania hollow spheres.
We will also provide an outlook of the exciting properties of such hierarchically structured porous titania materials with respect to their optical and thermal transport properties.