Low Temperature Hydrothermal Synthesis and Characterization and Optical Properties of Sr5Nb4O15 - Nb2O5 Nanocomposite

Sr5Nb4O15 – Nb2O5 nanocomposites were synthesized in 2 and 4 M KOH aqueous solutions, via a non-stoichiometric 1:2 Sr:Nb molar ratio hydrothermal method at 160°C for 48 h (S1 and S2, respectively). Sr(NO3)2 and Nb2O5 were used as raw materials. The synthesized nanomaterials were characterized by powder X-Ray diffraction (PXRD) technique. It was found that Sr5Nb4O15 has been crystallized in hexagonal crystal structure with space group P-3m1. Nb2O5 lattice parameters were also found as a= 6.175 Å, b= 29.175 Å, and c= 3.93 Å and a= 12.73 Å, b= 5.56 Å, and c= 4.88 Å with γ= 105.1°, respectively for the orthorhombic and monoclinic crystal structures. The morphologies of the synthesized materials were studied by field emission scanning electron microscope (FESEM). The FESEM images showed that the S1 and S2 nanocomposites had flower and plate like structures, respectively. Ultraviolet–Visible (UV-Vis) spectra analyses showed that the synthesized nanocomposites had strong light absorption properties in the ultraviolet light region. FTIR spectra of the obtained nanomaterials were also studied. Cell parameter refinements of the synthesized nanocomposites were also investigated.