Ammonium oxotrifluorotitanate: morphology control and conversion to anatase TiO2



Uniform ammonium oxotrifluorotitanate (NH4TiOF3) mesocrystals were synthesized from an aqueous solution containing (NH4)2TiF6 and H3BO3 in presence of nonionic surfactant. Effects of various reaction conditions on the morphology of the NH4TiOF3 mesocrystals were examined by electron microscopy techniques. Results indicate that static solution, high surfactant concentration and low reaction temperature enhance the formation of uniform NH4TiOF3 mesocrystals with regular shapes. By sintering in atmosphere, the NH4TiOF3 mesocrystals were converted to anatase TiO2, which retain the original shapes of the NH4TiOF3 precursor due to similarities on their atom structures. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)