Structure, Morphology and Spectroscopy Characterization of the Lа1-X-YErx/2Eux/2CayVO4 Sol-Gel Nanoparticles

The lanthanum vanadate nanoparticles doped with europium and erbium ions and co-doped with calcium ions were prepared by aqueous nitrate-citrate sol-gel synthesis route taking citric acid as a complexing agent. Phase composition, crystal lattice parameters and microstructure of the synthesized samples were established using various methods. The XRD analysis has revealed dependence of crystal structure on dopants concentration: monoclinic monazite-type structure for low dopant concentrations and tetragonal zircon-type structure for high dopant concentrations. The photoluminescence emission spectra are presented by narrow lines caused by f-f transitions in the rare earth activators. The relations between crystal phase structures and luminescence properties were discussed.