Phase Equilibria in the System ZnO—TiO₂

Abstract

The system ZnO-Ti02 has been investigated using quenching, hydrothermal, strip-furnace, and solid-state-reaction techniques. Two compounds were found: Zn2Ti04, which melts congruently at 1549"C., and ZnTiOs, which dissociates hydrothermally at 945°C. to give Zn2Ti04 and rutile. Two eutectics were found: one between ZnO and Zn2Ti04 at 32 mole % TiO, and 1537°C. and the other between ZnzTiOl and TiO? at 58 mole yo Ti02 and 1418°C. Rutile was the only modification of TiO, observed. The reported melting points of ZnO and TiO, are 1975" and 1830°C. respectively; however, data exist which indicate the sublimation of ZnO at atmospheric pressure. Loss of ZnO by volatilization slightly decreased the accuracy of the liquidus relations. Reported solid solutions of TiO, in Zn2Ti04 and ZnTiOs were not encountered, and explanations of this discrepancy are proposed.

Large decrease in the critical temperature of superconductingLaFeAsO0.85compounds doped with 3% atomic weight of nonmagnetic Zn impurities

“…The EPMA analysis entirely supports the result. Usually, loss of ZnO becomes significant during heating above 1100°C by volatility, 42 thus experimental chances of Zn substitution to an oxide is often limited. Perhaps, the high-pressure condition might allow us to reduce the ZnO volatility during heating, resulting in the successful Zn substitution to LaFeAsO 0.85 .…”

Dielectric properties of zinc titanate thin films prepared by Rf magnetron sputtering

“…Basic studies regarding the phase diagram and the physical properties of ZnO-TiO2 system have been published since 1960s [1,2]. Much attention has been still paid because of its diverse electrical and chemical properties, leading to the wide applications in sensors, microelectronics and high performance catalysts [3][4][5][6].…”

“…Recently, the zinc titanate ceramics have been promisingly reported as microwave dielectric materials due to their stable and proper dielectric properties [7][8][9]. Dulin and Rase [1] showed that three compounds exist in the ZnO-TiO 2 system, including Zn 2 TiO 4 (cubic), ZnTiO 3 (hexagonal), and Zn 2 Ti 3 O 8 (cubic). Zn 2 TiO 4 phase can easily be prepared by conventional solid-state reaction.…”

The additive influence on sintering of ZnO-TiO2 system according to triad ?synthesis-structure-properties?

“…Dijagram stanja sistema ZnO-TiO 2 još od 1960. godine [49] privlači pažnju istraživača upravo zbog njegovog značaja za praktičnu primenu (sl. 1.14.).…”

“…1.14. Dijagram stanja sistema ZnO-TiO 2 [49] Detaljno proučavanje električnih svojstava ovih materijala dovelo je do njihove široke primene u čvrstim oksidnim gorivim ćelijama, gasnim senzorima, mikroelektronici i katalizatorima visokih performansi za kompletnu oksidaciju ugljen-monoksida i redukciju azot-monoksida [62][63][64].…”