The mixed zirconium, titanium, hafnium and first-row transition metal oxides (containing phosphorous oxide) were prepared
using ion exchange method followed by calcinations at 1020 K during 12 h. The resulted mixed oxides were identified by XRPD
method and studied their thermal behaviour by TG-DTA analysis. As a result of thermal analysis there were found one exothermic
(with a peak at about 950 K), and one endothermic (with a peak at about 1300 K) processes, both without mass loss. The observation
was valid for all investigated samples.
The analysis of XRPD patterns of the investigated samples showed well-defined crystal phases characteristic of each oxide.
The XRPD analysis also verified the phase transition of tetravalent metal oxides from orthorhombic to tetragonal, observed
by DTA analysis.