Phonon confinement effects in the Raman scattering by TiO2 nanocrystals

  title={Phonon confinement effects in the Raman scattering by TiO2 nanocrystals},
  author={Danilo Bersani and Pier Paolo Lottici and Xing-zhao Ding},
  journal={Applied Physics Letters},
Nanocrystalline TiO2 has been obtained by a sol-gel process by controlling the crystal size through the water/alkoxide ratio. Raman spectra of anatase nanocrystals with average sizes of 9.5–13.4 nm are reported and the correlation between the Raman band shape (peak position and linewidth) of the main feature at 144 cm−1 and the crystals dimension is discussed. While in this system a minor role is played by nonstoichiometry and pressure effects, a model based on the phonon confinement, which… Expand
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