Sol–gel synthesis, characterization, and optical properties of Gd3+-doped CdO sub-micron materials

Highly crystalline Gd 3+ -doped cadmium oxide micro-structure was synthesized by calcining the obtained precursor of a sol–gel reaction. The reaction was carried out with cadmium nitrate (Cd(NO 3 ) 2 ·4H 2 O), gadolinium oxide, and ethylene glycol (C 2 H 6 O 2 ) reactants without any additives at 80°C for 2 h. The resulting gel was calcined at 900°C with increasing temperature rate of 15°C/min for 12 h in a furnace. As a result of heating, the organic section of the gel was removed, and the Gd 3+ -doped cadmium oxide micro-structure was produced. The obtained compound from the sol–gel technique possesses a cubic crystalline structure at a micro scale. XRD study indicates that the obtained Gd 3+ -doped CdO has a cubic phase. Also, the SEM images showed that the resulting material is composed of particles with cluster structure. Also, FT-IR spectroscopy was employed to characterize the Gd 3+ -doped CdO micro-structures.