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sample. The prepared sample is further annealed at 300℃ and 600℃ for 3h in furnace named

as S1 and S2, respectively.
Characterizations

The ready samples are characterized by best suitable experimental technique as like: XRD,
TEM, UV-Visible and Fluorescence. XRD sequence obtained through X’PERT PRO X-Ray

Diffractometer which operated at 45kV and 40 mA with Cu Kα monochromatic energy of
wavelength 1.540 Å. Thermally treated sample at the temperature of 300℃ and 600℃

produced nanoscale crystal structure morphology using Hitachi-4500 TEM. Optical

absorption spectra are obtained in wavelength range ~ 200-900 nm via Perkin Elmer Lambda
750 spectrophotometer. Finally, the last but not least fluorescence spectra originate by Perkin

Elmer Fluorescence spectrometer (model LS-55).

RESULTS AND DISCUSSION
X-Ray Diffraction (XRD) Analysis

The obtained XRD sequence for thermally treated samples S1 and S2 of samarium doped
silica nanopowder is displays in Fig. 1. There was no specific crystalline phase observed in

sample S1 which is annealed at 300℃. This type of XRD sequence with broad hump and
irregular peaks strictly verifies the amorphous nature of sample. Broad hump originates at 2θ

~ 22.63° and 45.41° recognized to amorphous silica in sample S1 (300℃) linked to JCPDS

card no. 29-0085 [11]. Amorphous nature of sample S1 create due to majority of precursors
and impurities at ow annealed temperature (300℃). The small hump about 2θ ~ 43.6°,

3+
displays that the activator ion (Sm ) can be arbitrarily dispersed in the SiO2 network [12].
As we increase the annealed temperature from 300℃ to 600℃, some interesting changes are

obtained in the XRD sequence of sample S2. The wide bands are almost disappeared in
sample S2 when the sample is thermally treated at 600℃ which give indication about the

well dispersion of samarium ions in the pore of silica networking structure.

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