Temperature dependence of the lowest frequency Eg Raman mode in laser-synthesized anatase TiO2 nanopowder
- First Online:
- Cite this article as:
- Šćepanović, M., Grujić-Brojčin, M., Dohčević-Mitrović, Z. et al. Appl. Phys. A (2007) 86: 365. doi:10.1007/s00339-006-3775-x
- 225 Downloads
Nanosized titanium dioxide (TiO2) powder was prepared by a laser-induced pyrolysis. Specific surface area of the as-grown powder measured by BET method was 109 m2/g. The grain size (14.5 nm) estimated from these data coincides well with the crystallite size (12.3 nm) determined by XRD measurements. The average grain size (∼35 nm) obtained from the subsequent SEM measurements refers to considerable agglomeration of nanoparticles. Raman spectroscopy has been used to investigate the structural properties of TiO2 nanopowder and its anatase structure is confirmed. The blueshift and broadening of the lowest frequency Eg Raman mode at temperature range ∼25–550 K have been analyzed using a phonon-confinement model. Dominant influence of the strong anharmonic effect at higher temperatures was demonstrated.