The raman spectra and X-ray powder diffraction data of stabilized hafnia phases

Raman spectra and X-ray powder diffraction data were measured for various compositions of Y₂O₃-doped hafnia, and interpreted on the basis of the growth of a stabilized hafnia phase apparently possessing tetragonal distortion with increasing dopant concentration. In contrast to the results for pure zirconia, there was no evidence in the Raman spectra or powder X-ray diffraction patterns to indicate the formation of a small particle size-stabilized tetragonal hafnia phase when X-ray amorphous hafnium hydroxide was heated at 425–600°C.