Electrical properties of Nb-doped titanium dioxide TiO2 at room temperature

• Autorzy: Trenczek-Zając A. , Rekas M.
• Konferencja: IX National Conference on Fast Ion Conductors , Wrocław-Borowice , 9-12 December 2004
• Języki publikacji: EN

Abstrakty

EN

Nb-doped TiO2 (0-15 at. % Nb) polycrystalline specimens were prepared by the sol-gel method. Below 10 at. % of Nb, materials were homogeneous and exhibited rutile structure, their lattice parameters changing with Nb concentration according to the Vegard's law. Above 10 at. % of Nb, the second phase TiNb2O7 was formed, detected by X-ray diffractometry. Materials were heated at 1273 K for 3 h in air (pO2 = 210 kPa) and in flow of Ar + 3 vol. % H2 gas mixture (pO2 = 10-15 Pa) and then cooled down. Electrochemical impedance spectroscopy within the frequency range 0.01 Hz-2 MHz has been used to determine electrical properties of the materials. An equivalent circuit composed of a resistor Rgb, a capacitor C connected parallel and a resistor Rb connected in series, well represents the electrical properties of reduced samples. On the other hand, non-Debye elements should be taken into account in construction of the equivalent circuit of oxidized materials. The mechanism of the Nb incorporation has been proposed.

Słowa kluczowe

EN

titanium dioxide; Nb-doping; solid solution; defect structure; impedance spectroscopy

PL

ditlenek tytanu; dwutlenek tytanu; roztwór stały; defekty struktury; domieszkowanie; niob; spektroskopia impedancyjna

• Wydawca: De Gruyter
• Czasopismo: Materials Science Poland
• Rocznik: 2006
• Tom: Vol. 24, No. 1
• Strony: 53--60
• Opis fizyczny: Bibliogr. 16 poz.

Twórcy

autor

Trenczek-Zając A.

autor

Rekas M.

• AGH University of Science and Technology Faculty of Materials Science and Ceramics, al. Mickiewicza 30, 30-059 Kraków,

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