Synthesis and characterisation of porous and non-porous monodisperse TiO2 and ZrO2 particles

Monodisperse spherical titania and zirconia particles of variable sizes are produced in a sol–gel synthesis from metal tetraalkoxides in alcohol with addition of a salt or a polymer solution. The influence of various precursor concentrations and the addition of different salt ions or polymer molecules on the size and on the size distribution of the final particles was investigated. The particles were characterised by electron microscopy, thermogravimetry, X-ray diffraction and electrophoresis. Nitrogen absorption measurements revealed that in the case of titania the addition of polymers yielded porous titania colloids.