CHEM01200604004 Shri Sanyasinaidu Boddu - Homi Bhabha ...

value. The lattice parameters calculated from the XRD patterns increase with increasing In 3+
content in the ample. This is understandable as the ionic size of In 3+ (0.81) is larger than that
of Ga 3+ (0.6) and incorporation of In 3+ at Ga 3+ site leads to lattice expansion thereby shifting
the diffraction peak maximum to lower 2θ value. The broadening of the diffraction peaks can
be attributed to the distortion in the lattice brought about by incorporation of larger ionic radii
In 3+ at the expense of Ga 3+ . Thus based on XRD studies it is confirmed that In 3+ gets
incorporated into the ZnGa 2 O 4 lattice and forms solid solutions of type ZnGa 2-x In x O 4 .
ZnGa 1.5
In 0.5
O 4
Intensity(arb.units)
ZnGa 1.7
In 0.3
O 4
ZnGa 1.8
In 0.2
O 4
ZnGa 1.9
In 0.1
O 4
ZnGa 1.95
In 0.05
O 4
ZnGa 2
O 4
20 30 40 50 60 70
2θ/ ο
Fig.98. XRD patterns of ZnGa 2-x In x O 4 (x = 0, 0.05, 0.1, 0.2, 0.3, 0.5) nanoparticles.
TEM image of ZnGa 1.5 In 0.5 O 4 nanoparticles is shown in Fig.99. Very fine particles
with size in the range of 4-6 nm can be seen in the image. Corresponding SAED pattern is
shown in the inset of the Fig.99 (a). The SAED pattern has been conformity with the
formation of nanocrystalline ZnGa 2-x In x O 4 phase.
Emission spectra of these samples are given in the Fig.100 (a). It is clearly seen that
the emission maximum is shifted towards higher wavelength side from 430 to 455 nm with
increase in the In 3+ content in the sample and this has been attributed to the presence of In 3+
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