The bands for all the samples are broad, which can be attributed to random distribution of Zr4+ and Ti4+ ions in equivalent sites of crystal lattice, oxide defects and nonstoichiometric variations of Zr/Ti ratio in polycrystalline ceramics [13,14]. Number of resolved Raman bands varies with sintering time, indicating differences in structural order [13].
We observed lower number of the bands, which can be explained by overlapping of the
broadened bands. The randomly distributed cations Zr4+ and Ti4+ within M-site in the crystal structure influence the band broadening. Moreover, since the ceramics was prepared from high-energy ball milled precursor, the oxide defects and nonstoichiometric variations of Zr/Ti ratio are also expected [16, 17].