Synthesis, processing and characterization of nanocrystalline titanium dioxide

Nanocrystalline titanium dioxide (TiO2) powder was synthesized by using a simple sol–gel technique, which can be easily controlled and reproduced. By hydrolyzing titanium tetraisopropoxide in a mixture of isopropanol and deionized water, TiO2 nanopowder was obtained after calcination at 400 °C. The powder was analyzed for its phases using X-ray diffraction technique and found to be pure anatase. Crystallite size, powder morphology and lattice fringes were determined using high-resolution TEM. DSC and TGA were used to study the thermal properties. As-synthesized powder was uniaxially compacted and sintered at 1300–1600 °C to investigate densification behavior and mechanical properties. Maximum hardness (472 ± 30 HV) and the best sintered density (3.75 g/cm3) were attained in structures sintered at 1600 °C, whereas, the highest compressive strength (364 ± 11 MPa) was achieved in structures sintered at 1500 °C.