Effect of Crystal Imperfections on Reactivity and Photoreactivity of TiO₂(Rutile) with Oxygen, Water, and Bacteria

Hydrostatic and [001] Uniaxial Pressure on Anatase TiO2 by Periodic B3LYP-D* Calculations

“…This happened because they are very dependent on the equatorial bonds; besides the constants C 12 and C 13 were softened under the pressure. The E g(1) had a sequence of red shift (compared with the undistorted structure) → blue shift → red shift (compared with the last compressed structure) by the same explanation as the red shift behavior for E g (3) . The difference between those two modes is that the principal vectors in E g (3) are in lighter atom (O), whereas for Sekiya et al 57 investigated the influence of pressure up to 6.7 GPa applied to anatase TiO 2 by Raman spectroscopy and observed that frequencies changed linearly within the pressure and most modes had a blue shift.…”

“…The E g(1) had a sequence of red shift (compared with the undistorted structure) → blue shift → red shift (compared with the last compressed structure) by the same explanation as the red shift behavior for E g (3) . The difference between those two modes is that the principal vectors in E g (3) are in lighter atom (O), whereas for Sekiya et al 57 investigated the influence of pressure up to 6.7 GPa applied to anatase TiO 2 by Raman spectroscopy and observed that frequencies changed linearly within the pressure and most modes had a blue shift. However, they also observed that E g (2) frequencies decreased under hydrostatic pressure and stated that this mode played an important role in the pressureinduced phase transition (that occurred at 4.3 GPa).…”

Niobium Segregation in Niobium-Doped Titanium Dioxide (Rutile)

“…16−19 It has also been documented that the semiconducting properties of TiO 2 are closely related to its defect disorder. 20,21 An accumulation of empirical data on defect-related properties of TiO 2 has resulted in the determination of equilibrium constants for the formation of intrinsic defects in TiO 2 , which are shown in Table 1. 21 These data and the associated charge neutrality conditions have been used in derivation of defect disorder diagrams that represents the effect of oxygen activity on the concentration of both electronic and ionic defects.…”

Experimental and theoretical approach of nanocrystalline TiO2 with antifungal activity

“…Theories about the microbial activity of TiO 2 are dependent on the light-induced reactivity of the TiO 2 photo-catalyst with water produces active species such as hydroxyl radicals, superoxides and hydrogen peroxide [41,42]. Gurr et al [43] demonstrated that small (10 nm to 20 nm) TiO 2 particles also induce lipid peroxidation, micronuclei formation as well as increased hydrogen peroxide and nitric oxide production in a human bronchial epithelial cell line even in the absence of photoactivation.…”