Preparation and Characterization of Single-Modified TiO2 for Pigmentary Applications

In the present work the influence of different additives, calculated to ZrO 2, ZnO, and B 2 O 3, on the anatase–rutile phase transformation was investigated. The chemical composition of prepared titania samples was determined by the selective leaching method, powder X-ray diffraction analysis, and FT-IR measurements. The effect of small amounts of additives on the optical properties, photoactivity, and surface area of rutile-phased TiO 2 for pigmentary applications was examined using spectrophotometer, SEM, and BET measurements. ZrO 2 acted as an inhibitor of the TiO 2 phase transformation and the addition of ZnO or B 2 O 3 to TiO 2 accelerated rutile formation at 750 °C. ZrO 2 addition in TiO 2 could form separate ZrO 2 phase and solid solution of Zr with Ti. Zinc partly reacted with titanium forming cophase TiZn 2 O 4 . Boron was located in TiO 2 in the form of soluble compound, B 2 O 3 . Almost all optical properties were lower for modified TiO 2 in comparison with the corresponding unmodified sample. The S BET increased with increase of ZrO 2 in TiO 2 and decreased with the increase of ZnO in TiO 2 . The photoactivity depended on the kind and contents of introduced additive and was lower for TiO 2 modified with ZrO 2 or ZnO than for TiO 2 –B 2 O 3 .