Solvothermal synthesis of micron-sized spherical particles in TiO_2-ZrO_2 binary system

摘要

We prepared TiO_2-ZrO_2 binary oxide particles with various Ti/(Zr+Ti) mole ratios (x) from the solutions containing Ti(OC_3H_7)_4, Zr(OC_3H_7~n)_4 and acetylacetone (acac). The spherical particles of 1-5 urn in diameter were obtained via solvothermal treatment at 150 ℃. The spheres were anatase at x=l and amorphous at x=0-0.8. The spheres were thought to be formed through the moderate hydrolysis and nucleation provided by the chelation of the alkoxides by acac. Crystalline TiO_2-ZrO_2 particles were obtained by the heat treatment of the as-precipitated spheres, and the crystalline phase changed with the Ti/(Zr+Ti) mole ratios. Pure ZrO_2 and TiO_2, ZrO_2 doped with Ti~(4+), TiO_2 doped with Zr~(4+) and ZrTiO_4 phases were produced, and the spherical shape remained after the heat treatment at 500-750 ℃.