Pure titania, zirconia, and mixed oxides (3-37 mol.% of ZrO2) are prepared using the sol-gel method and calcined at different temperatures. The calcined samples are characterized by Raman spectroscopy, X-ray powder diffraction, scanning electron microscopy, transmission electron microscopy, and nitrogen adsorption porosimetry. Measurements reveal a thermal stability of the titania anatase phase that slightly increases in the presence of 3-13 mol.% of zirconia. Practically, the titania anatase-rutile phase transformation is hindered during the temperature increase above 700°C. The mixed oxide with 37 mol.% of ZrO2 treated at 550°C shows a new single amorphous phase with a surface area of the nanoparticles double with respect to the other crystalline samples and the formed srilankite structure (at 700°C). The anatase phase is not observed in the sample containing 37 mol.% of ZrO2. The treatment at 700°C causes the formation of the srilankite (Ti0.63Zr0.37Ox) phase.
PHASE FORMATION IN MIXED TiO2–ZrO2 OXIDES PREPARED BY SOL-GEL METHOD / E., Kraleva; M. L., Saladino; Matassa, Roberto; E., Caponetti; S., Enzo; A., Spojakina. - In: JOURNAL OF STRUCTURAL CHEMISTRY. - ISSN 0022-4766. - 52:2(2011), pp. 330-339. [10.1134/s0022476611020132]
PHASE FORMATION IN MIXED TiO2–ZrO2 OXIDES PREPARED BY SOL-GEL METHOD
MATASSA, ROBERTO;
2011
Abstract
Pure titania, zirconia, and mixed oxides (3-37 mol.% of ZrO2) are prepared using the sol-gel method and calcined at different temperatures. The calcined samples are characterized by Raman spectroscopy, X-ray powder diffraction, scanning electron microscopy, transmission electron microscopy, and nitrogen adsorption porosimetry. Measurements reveal a thermal stability of the titania anatase phase that slightly increases in the presence of 3-13 mol.% of zirconia. Practically, the titania anatase-rutile phase transformation is hindered during the temperature increase above 700°C. The mixed oxide with 37 mol.% of ZrO2 treated at 550°C shows a new single amorphous phase with a surface area of the nanoparticles double with respect to the other crystalline samples and the formed srilankite structure (at 700°C). The anatase phase is not observed in the sample containing 37 mol.% of ZrO2. The treatment at 700°C causes the formation of the srilankite (Ti0.63Zr0.37Ox) phase.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.