Authors: Z. Zhang, J.A. Darr
Affilation: University College London, United Kingdom
Pages: 680 - 683
Keywords: contineous hydrothermal synthesis, TiO2, photocatalysts, dielectric, nitridation of TiO2
we have adopted a novel approach to the use of continuous hydrothermal flow system (CHFS) for the synthesis of various crystalline doped anatase TiO2 nano-ceramics with high surface area (ca. 280 m2g-1) system. Their photocatalytic activities and dielectric properties have been examined. Certain doped materials with high photocatalytic activities generally displayed better dielectric quality factors with relatively low microwave dielectric loss, when they were sintered at low temperature (950 oC) for 2 h. Furthermore, a simple method for the synthesis of nanocrystalline nitrogen-doped TiO2 has been developed. This process is based on the heat treating CHFS synthesized nano-TiO2 in an ammonia/argon atmosphere.Nitrogen-doped TiO2 with a homogeneous anatase phase and small particle size was obtained under the nitridation temperatures between 400 to 700 oC. Doped powders prepared at 600 oC had the best photocatalytic activity.Phase pure titanium nitride (TiN) has also been obtained at a nitridation temperature of 1000 oC for 5 hours.