White light emission from Eu3+ in CaIn2O4 host lattices

Ca In 2 O 4 : x Eu 3 + (x=0.5%,1.0%,1.5%) phosphors were prepared by the Pechini sol-gel process [U.S. Patent No. 3,330,697 (1967)] and characterized by x-ray diffraction and photoluminescence and cathodoluminescence spectra as well as lifetimes. Under the excitation of 397nm ultraviolet light and low voltage electron beams, these phosphors show the emission lines of Eu3+ corresponding to D0,1,2,35-FJ7 (J=0,1,2,3,4) transitions from 400to700nm (whole visible spectral region) with comparable intensity, resulting in a white light emission with a quantum efficiency near 10%. The luminescence mechanism for Eu3+ in CaIn2O4 has been elucidated.