Mechanochemical synthesis of Bi4Ti3O12

Our efforts were directed to the preparation of bismuth titanate - Bi 4e;Ti3O12 (BIT) by mechanically assisted synthesis. The mechanical activation was applied to prepare bismuth titanate, Bi4e;Ti3O12, from bismuth oxide, Bi 2O3, and titanium oxide, TiO2 (in an anatase crystal form). Mechanochemical synthesis was performed in a planetary ball mill in air atmosphere. Bismuth titanate ceramics was obtained by sintering at 1000° C The formation of Bi4e;Ti3O12 in the sintered samples was confirmed by X-ray diffraction analysis. Scanning electron microscopy, SEM, was used to study the particle size and powder morphology. The obtained results indicate that Bi4e;Ti3O12 from the powder synthesized by high-energy ball milling exhibits good sinterability, showing advantage of the mechanochemical process over conventional solid-state reaction.

Static simulation of bulk and selected surfaces of anatase TiO2

A theoretical investigation has been carried out to characterize bulk and selected surfaces of anatase TiO2. The calculations are performed using a B3LYP hybrid functional and 6-31G basis set within the periodic density functional approximation. Optimization procedures have been employed to determine the equilibrium geometry of the crystal and slab surface models. The compressibility, band structure, and the bulk and surface charge distributions are reported. The surface relative energies are identified to follow the sequence: (001) < (101) < (100) much less than (110) < < < (111), from the most stable surface to the least stable one. Relaxation of (001) and (101) surfaces are moderate, with no displacements exceeding; approximate to0.19 Angstrom. The theoretical results are compared with previous theoretical studies and available experimental data. (C) 2001 Elsevier B.V. B.V. All rights reserved.

DFT Study with Inclusion of the Grimme Potential on Anatase TiO2: Structure, Electronic, and Vibrational Analyses

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Propriedades estruturais e eletrônicas de nanofilmes de TiO2 anatase: cálculos B3LYP-D* em sistemas periódicos bidimensionais

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Biomarker evaluation in fish after prolonged exposure to nano-TiO2: influence of illumination conditions and crystal phase

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)