CHEM01200604004 Shri Sanyasinaidu Boddu - Homi Bhabha ...

atoms at three corners and the lone pair of electrons of antimony at the fourth corner with all
the O - Sb - O bond angles different [178].
In spite of significant difference in terms of ionic radius, electro-negativity,
coordination numbers between Sb 3+ and Eu 3+ ions, it is of interest to understand the chemical
interaction taking place between them, particularly in aqueous/organic solvents under
alkaline conditions. This is because many technologically important luminescent oxide
nanoparticles doped with lanthanide ions and Sb 3+ are prepared under these conditions. For
example Wen, et al. [179] have demonstrated that by suitably modifying Eu 3+ /Sb 3+ ratio in
YBO 3 crystal, nearly white light emission can be obtained. Their interaction under high
temperature heat treatment is also important as lanthanide ions are co-doped with Sb 3+ ions in
several oxide-based glasses, which are prepared at high temperatures [180, 181]. It is reported
that presence of Sb 2 O 3 in silicate glass doped with Er 3+ , has significant effect on spontaneous
emission rates of 4 I 13/2 level of Er 3+ in the glass [180]. Hence, it is of interest to understand the
optical properties of the Sb 2 O 3 synthesised in both the presence and absence of lanthanide
ions in detail.
In the first section of this chapter, effect of lanthanide ion (Eu 3+ , Tb 3+ and Dy 3+ )
incorporation on the structural and morphological aspects of GaOOH nanorods has been
presented. As the luminescence properties of Eu 3+ ions with respect to its environment are
well understood, it has been used as a probe to monitor the structural changes taking place
with GaOOH lattice brought about by lanthanide ion incorporation. In the second section of
this chapter, the photoluminescence and structural properties of Sb 2 O 3 nanorods oriented
along a particular direction and their interaction with lanthanide ions are discussed. The shape
selective modifications in the structure and luminescence properties of the nanorods as well
as the interaction of nanorods with lanthanide ions have been investigated using X-ray
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