CHEM01200604004 Shri Sanyasinaidu Boddu - Homi Bhabha ...

is almost 1½ times that of peak B1 and B3. As the samples are annealed (say at 100°C and
200°C), these peaks are merged and appear as a one single peak similar to the one observed
from the bulk sample. The morphology change is further clear from the shoulder peak ~ 710
cm -1 (as shown by the encircled region in Fig.45 (d)) observed for nanorods, which is
successively broadened with increasing annealing temperature.
Fig.45. Raman spectrum of (a) as prepared Sb 2 O 3 nanorods. The changes related to
morphology/annealing are shown by arrows at ~260 cm -1 and ~445 cm -1 . Enlarged
view of the Raman spectrum corresponding to Sb–O–Sb stretching (b, d) and
bending (c) modes of Sb 2 O 3 nanorods annealed at various temperatures along with
that of bulk sample are also shown. Fig.45 (b) shows peaks ‘A1’ and ‘A2’ for the
260 cm -1 peak and Fig.45 (c) shows ‘B1’, ‘B2’ and ‘B3’ for the 445 cm -1 peak.
Encircled region in Fig.45 (d) shows the changes in the Sb–O–Sb stretching
vibrations at various annealing temperatures.
The Sb 2 O 3 comprises of four SbO 3 (E) pyramids (E being lone pair of electrons) arranged
into the Sb 4 O 6 molecular ring structure with a Td symmetry [209,210]. Each oxygen is
bridged between two SbO 3 pyramids. According to Gilliam, et al. [210], the molecular
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