CHEM01200604004 Shri Sanyasinaidu Boddu - Homi Bhabha ...

transferred into a two-necked RB flask. An aqueous solution (3 ml) of ammonium
dihydrogen phosphate (0.3 g) was added with stirring. The solution was heated at different
temperatures viz. 75, 100, 125 and 185°C for two hours. The precipitate obtained was washed
with methanol and acetone to remove unreacted species and dried under ambient conditions.
The same procedure was followed for the synthesis of other lanthanide ions doped samples.
2.5 Synthesis of gallate nanomaterials:
Synthesis of undoped, In 3+ and Ln 3+ doped ZnGa 2 O 4 nanoparticles: For the preparation
of ZnGa 2 O 4 nanoparticles gallium metal and Zinc acetate were used as starting materials.
Gallium metal (0.2 g) was dissolved in concentrated HCl containing few drops of HNO 3 in a
beaker and the excess acid was removed by repeated evaporation by adding water. This
solution was transferred into a two-necked RB flask, containing appropriate amount of zinc
acetate. Ethylene glycol (25 ml) and distilled water (10 ml) were added to this mixture. The
solution was slowly heated up to 100°C followed by the addition of urea (3.0 g). It was
heated at 120°C whereupon turbidity appeared. Temperature of the reaction was maintained
for 2 hours to complete the reaction. The precipitate was collected by centrifugation and then
washed three times with ethyl alcohol and two times with acetone followed by drying under
ambient conditions. This process was repeated for different ratios of solvent to precursor
concentration as well as ethylene glycol to water. For In 3+ , Eu 3+ and Tb 3+ doped samples
same procedure was followed except addition of appropriate amounts of InCl 3 , Eu 2 O 3 and
Tb 4 O 7 was carried out while dissolving gallium metal in concentrated HCl.
Preparation of In 3+ doped ZnGa 2 O 4 nanoparticles incorporated PMMA matrix: For
incorporating nanoparticles in polymer, the procedure reported by Gonsalves, et al. [115] was
employed. The method is described below. Around 50 mg of ZnGa 2 O 4 nanoparticles was
dispersed in one ml of methyl methacrylate (MMA) by sonicating for one hour under argon
atmosphere. Around 5 mg of azobisisobutyronitrile (AIBN) was added to this mixture and
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