CHEM01200604004 Shri Sanyasinaidu Boddu - Homi Bhabha ...

500°C and monoclinic β-Ga 2 O 3 at 900°C as can be seen from the XRD patterns (Fig.31). All
the diffraction peaks have been assigned to corresponding planes. Average crystal size was
calculated by using Debye-Scherrer formula and is 40 nm for GaOOH, 22 nm for α-Ga 2 O 3
and 19 nm for β-Ga 2 O 3 . In order to check morphology changes occurring during heat
treatment, SEM measurements were carried out and are shown in Fig.32. From these images
it is clear that rod shape morphology of GaOOH is maintained even after heat treatment to
form α- and β-Ga 2 O 3 phases.
Intensity (arb.units)
(201)
(020)
(012)
(110)
(120)
(104)
(110)
GaOOH
β - Ga 2
O 3
(400)
(202)
(111)
(401) (111)
(311)
(311)
(312)
(510)
(113)
α - Ga 2
O 3
(024)
(116)
(130)
(021)
(111)
(121)
(140)
(131)
(041)
(211)
(221)
(313)
(018)
900 o C
(020)
(512)
500 o C
(214)
(300)
(231)
(151)
(002)
(061)
20 30 40 50 60 70
2θ/ ο asprepared
Fig.31. XRD patterns of as prepared, 500 and 900°C heated GaOOH nanorods
(a)
(b)
Fig.32 SEM images of GaOOH nanorods heated at (a) 500°C and (b) 900°C
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