Zirconium dioxide (ZrO2), also known as zirconia, is a white crystalline oxide of zirconium. It exists in three phases: monoclinic 2,370 °C. A small quantity of yttrium, calcium or magnesium can stabilize the tetragonal and cubic phases so that the remain stable at normal conditions. By adding e.g. yttria (Y2O3), the phase changes are eliminated, and the resulting material has superior thermal, mechanical, and electrical properties. Zirconia is chemically unreactive. It is slowly attacked by concentrated hydrofluoric acid and sulfuric acid. When heated with carbon, it converts to zirconium carbide. When heated with carbon in the presence of chlorine, it converts to zirconium tetrachloride.
PlasmaChem offers zirconium oxide nanoparticles in all three phase types. Besides, the specially designed nanoparticles were developed, which can form colloids in water or in organic solvents. The size of ZrO2 nanoparticles in such colloids is ca. 3 nm, which makes the dispersion almost infinitely stable against sedimentation.