Synthesis and characterization of NdxSr2As2O7+δ by solvothermal method

Mixed metal oxides have drawn considerable attention in many applications such as immobilization of fission products, catalysis [3], and solid electrolytes [10]. They have also been used in various environmental and bio-industrial applications such as in degradation of organic pollutants. The main objective of this study was to synthesize and characterization of NdxSr2As2O7+8 using As2O3, Sr(NO3)2 and Nd203 by solvothermal method (ratio H2O:Ethanol was 1:1) at 200 °C for 24 h( pH=12). The employed techniques are XRD, SEM and DRS. XRD pattern of powdered sample is presented in Fig. 1. Rietveld analysis showed that the obtained material was crystallized well in the monoclinic and tetragonal crystal structures . The crystallite size of the sample was calculated from X-ray lines broadening of the reflections of using Scherrer s equation(D=24 nm). Fig.2 shows the FESEM image of sample. It shows that the product is consisted of high-length rods and sheets. The optical properties of the obtained material showed that the material has strong absorption in UV light region. The direct optical band gap energies of the two samples show that there are two distinct band structures. So, two band gap energies are present in the spectra at about 3.00 and 3.40 eV.