EPR Study of TiO2 (Rutile) Doped with Vanadium

Resumo

Samples of titanium dioxide, TiO₂, doped with vanadium ions (0.1 ≤ [Vⁿ⁺]₀ ≤ 5.0 at. %) at high temperature, were prepared in a polycrystalline state and investigated using X-, Q-, and W-band electron paramagnetic resonance, EPR, spectroscopy. Substitutional and interstitial V⁴⁺ centers in TiO₂ lattice have been both observed in EPR spectra, and their spin-Hamiltonian parameters were calculated. Portions of paramagnetic and diamagnetic species of Vⁿ⁺ ions were estimated. The effect of additional high temperature annealing on the valence state of vanadium centers is discussed.