Synthesis and luminescence properties of Er3+ doped La3NbO7 ceramic powder

La3NbO7 compounds doped with Er3+ were synthesized by conventional solid state reaction. X-ray diffraction (XRD) and scanning microscopy (SEM-EDS) were used to analyze the morphology and microstructure of this ceramic powder. Rietveld's refinements show that the samples exhibit an orthorhombic weberite structure that can be described using the Cmcm spatial group. A gradual reduction of the unit cell (lattice parameters) with the erbium content evidences the effective substitution in the structure of La3+ ions with the smaller Er3+ ions. The erbium luminescence capabilities were studied using absorption and photoluminescence techniques in the visible (VIS) and near infrared (NIR) regions. The characteristic green, red and NIR Er3+ luminescence bands were obtained under excitation with several wavelengths in the VIS-NIR region, being characterized by a strong multicenter structure. Up-conversion luminescence channels have also been studied to put in value the potentiality of Er3+ doped La3NbO7 as a new phosphor.