Materials Today: Proceedings | 2019
Near ultraviolet excited down conversion Eu and Er co-doped CaAl2O4 color tunable nano-phosphors: Structural, morphological and photolumniscent characteristics
Abstract
Abstract A series of CaAl2O4:Eu3+ (1\u202fmol%) co-doped with Er3+ (0, 1, 2, and 5\u202fmol%) was synthesized by urea assisted combustion method at 600\u202f°C and further calcinations was done at 1000\u202f°C to enhance the crystalline character and luminescence properties. Synthesized samples were characterized structurally and optically using the X-ray diffraction (XRD) and spectrofluorometer respectively. From XRD analysis, monoclinic phase of CaAl2O4 is reported in all the samples indicating that doping of Eu3+ and Er3+ do not change the crystalline structure of calcium aluminate. Both Eu3+ and Eu2+ states were detected in the synthesized materials whose ratio changes with calcination as well as with co-doping of the Er3+ ions. CaAl2O4:Eu3+ (1\u202fmol%) synthesized at 600\u202f°C show high intense peak around 440\u202fnm due to presence of Eu2+ state, whose intensity decrease with co-doping and upon calcination where as at the same time intensity of peak in the red region due to the presence of Eu3+ increases. In the compounds calcined at 1000\u202f°C, electric dipole 5D0\u202f→\u202f7F3 transition of Eu3+ at 657\u202fnm appears as peak with highest intensity. The Er3+ ion acts as sensitizer and enhances the luminescent properties of co-doped samples.