The crystallization of HfO2 and ZrO2 under hydrothermal conditions (CROSBI ID 111871)
Prilog u časopisu | izvorni znanstveni rad | međunarodna recenzija
Podaci o odgovornosti
Štefanić, Goran ; Musić, Svetozar ; Molčanov, Krešimir
engleski
The crystallization of HfO2 and ZrO2 under hydrothermal conditions
Hydrothermal crystallization of hydrous hafnia at 90 and 120 oC, was monitored at pH 3, 7, 9.5 and 13, using X-ray powder diffraction analyses. The obtained results showed that hydrothermal crystallization proceeded much more slowely in a neutral pH medium than in an acidic or alkaline medium. Phase analysis of the products of hydrothermal treatment showed that, regardless of pH, hydrous hafnia crystallized into m-HfO2. Stabilization of metastable cubic or tetragonal HfO2 occured upon adding a sufficient amount of stabilizing Na+ ions. Similarities and differences between the hydrothermal crystallization of HfO2 and the hydrothermal crystallization reported for ZrO2 were discussed. It was concluded that in both cases hydrothermal crystallization proceeds via a dissolution/precipitation mechanism in the whole pH range.
hydrothermal crystallization ; HfO2 ; ZrO2 ; XRD ; Metastable phase
nije evidentirano
nije evidentirano
nije evidentirano
nije evidentirano
nije evidentirano
nije evidentirano
Podaci o izdanju
387 (1-2)
2005.
300-307
objavljeno
0925-8388
1873-4669
10.1016/j.jallcom.2004.06.064