Synthesis and characterization of a novel alkaline earth niobate Ca0.5Sr0.5Nb2O6

Ca0.5Sr0.5Nb2O6 (CSN), a novel compound with crystal structure similar to the well-known orthorhombic columbite compound CaNb2O6 (CN) of alkaline earth niobates family was synthesized by a simple co-precipitation technique. The synthesized material was characterized by using X-ray diffraction (XRD) technique, transmission electron microscopy (TEM), UV-Vis diffuse reflectance spectroscopy, FTIR spectroscopy, and photoluminescence emission spectroscopy. It was found that the CSN compound stabilizes in P b c n space group with the improved symmetry as compared to the CN. The lattice parameters of CSN were found to be comparable with those of CN, and they are: a = 15.013 angstrom, b = 5.757 angstrom and c = 5.198 angstrom. The morphology of CSN and CN particles synthesized by a similar method was found to be identical. However, in CSN stronger self activated luminescence than that of CN was observed. The self-activated luminescence property of CSN was assigned to the niobate octahedral group [NbO6](7-) similar to the CN. (C) 2015 Elsevier B.V. All rights reserved.