The reaction between (NH4)2TiF6 and H3BO3 in the presence of varying quantities of PEG-6000 was used to form NH4TiOF3 mesocrystals (MCs). The amount of PEG-6000, employed as a template, is crucial to the formation of defect free, non-agglomerated NH4TiOF3 MCs; high concentrations lead to MC agglomeration, lower ones result in centralized defects. This polymer-mediated formation process may be understood using an analogy with known polymerization reactions. The oxofluorotitanate MCs readily undergo a thermal topotactic transformation to give anatase MCs with photocatalytic activity. The TiO2 MCs are porous, with highly orientated lamellar crystallites that form part of the larger mesocrystal structure.
Olga, B. V., Sadovnikov, A. A., Yorov, K. E., Beltiukov, A. N., Baranchikov, A. E., Ivanov, V. K., Zhong, X., Lewis, D. J., O'Brien, P., & Sutherland, A. J. (2017). New insights into polymer mediated formation of anatase mesocrystals. Crystengcomm, 19(24), 3281-3287. https://doi.org/10.1039/C6CE01985D