X-ray diffraction study on pressure-induced phase transformations in nanocrystalline anatase/rutile (TiO2)

An in situ x-ray diffraction study was conducted to study the pressure-indu ced phase transformation in nanocrystalline anatase/rutile (TiO2) to 35.1 G Pa. The nano-anatase phase remains stable to approximately 16.4 GPa, and th en transforms to an amorphous phase, which is returned upon release of pres sure. The nano-rutile phase starts to transform to the baddeleyite (ZrO2,) structure at similar to8.7 GPa, and the transformation is complete at appro ximately 16.4 GPa. On release of pressure the ZrO2 structure transforms to the alpha -PbO2 structure. The results are compared to previous work on pha se changes in TiO2 with different particle sizes.