Among the great number of sol-gel materials prepared, TiO2 holds one of the most important places due to its photocatalytic properties, both in the case of powders and coatings. Impurity
doping is one of the typical approaches to extend the spectral response of a wide band gap semiconductor to visible light.
This work has studied some un-doped and Pd-doped sol-gel TiO2 nanopowders, presenting various surface morphologies and structures. The obtained powders have been embedded in vitreous
TiO2 matrices and the corresponding coatings have been prepared by dipping procedure, on glass substrates. The relationship between
the synthesis conditions and the properties of titania nanosized materials, such as thermal stability, phase composition,
crystallinity, morphology and size of particles, and the influence of dopant was investigated.
The influence of Pd on TiO2 crystallization both for supported and unsupported materials was studied (lattice parameters, crystallite sizes, internal
strains). The hydrophilic properties of the films were also connected with their structure, composition and surface morphology.
The methods used for the characterization of the materials have been: simultaneous thermogravimetry and differential thermal
analysis, powder X-ray diffraction, electron microscopy (TEM, SAED) and AFM.