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Excitation spectra for S2 at 410 nm
1000

800 (235 nm)

Intensity 600

400

200

0
210 240 270 300 330 360 390
Wavelength (nm)

Fig. 5: Excitation spectra of S2 sample for samarium doped silica nanopowder.
FL emission spectra is displays in Fig. 6 under the excitation wavelength 235 nm for the

thermal treated sample S2 at 600℃. On excitation, Sm2O3 doped SiO2 nanopowder displays
strong emission at different wavelength in the range 300-600 nm which corresponds to

different characteristic electronic transitions.

As we known that electrons regulate the transport possessions like electrical conductivity,
while there is no phenomenon correlated to holes have been detected. This defines that holes

are closely trapped around defects. Consequently, Si-O-Sm linkage is the chief factor in
present study to influence fluorescence [18].

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