Hello. Correct, it is electrically non-conductive material. It is good at standing high temperatures and it is mechanically very hard, thus it is applied in space shuttle industry. Cheers.
Doping Zirconia with Yttria (Y2O3) replaces Zr^4 with Y^3and adds Oxygen Vacancies.The substitution of Zr^4 with Y^3 causes the negative net charge in the lattice; for every mole of yttria incorporated into the zirconia lattice, the charge neutrality condition is kept by forming an oxygen vacancy whose Kroger-Vink notation notation it is written as follows:
Y2O3------2Y′Zr+3OxO+V¨O
Where Y′Zr means Y in the Zr site with the apparent negative charge, and V¨O is the vacancy in the oxygen site with double positive charge. Oxo is the lattice oxygen, i.e., oxygen in the oxygen site with net charge of zero(0). The electron get trapped in the vacancies created by the deficient oxygen. THE ELECTRONS THUS ENTRAPPED IN THE ANION VACANCIES CALLED { F- CENTERS}* ARE RESPONSIBLE BOTH FOR ITS ELECTRICAL CONDUCTION AND COLOR.
The maximum ionic conductivity lies around 8-9 mol% Y2O3 doping. At higher doping the attraction between the oxygen vacancies and the yttria will result in the formation of complexes and decreases the mobility of the oxygen vacancies.
* F- FARBE- a German word- means color.
[ASolid State Ionics
Volume 106, Issues 1–2, 1 February 1998, Pages 89–101.
Abstract
The electrical conductivity of yttria stabilized zirconia (YSZ), prepared by precipitation from aqueous solutions of inorganic precursors, was measured as a function of composition, temperature of annealing prior to conductivity measurements (900°C–1700°C), and temperature of measurement (500°C–900°C). A comparison is made with the more dense YSZ prepared by the dry powder method: the conductivites are very near when the same high annealing temperatures are applied. The considerable increase in the conductivity attained by raising the annealing temperature of the precipitated material is suggested to be largely due to an increase in density. The effect of other factors is considered.
[B] Also from Wikipedia
[C ]Jo urnal of Physics: Condensed Matter Volume 16 Number 23
Jean-Marc Costantini et al 2004 J. Phys.: Condens. Matter 16 3957.[Regarding its color]
band gap of YSZ is about 5 eV. In that case it can be called as a wide band gap semiconducor or even an insulator.
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