Photoluminescence properties of a novel rare-earth-free red-emitting Ca_3Y(AlO)_3(BO_3)_4:Mn~(4+) phosphor for white LEDs application

摘要

Novel red-emitting phosphors of Ca~(3)Y(AlO)~(3)(BO~(3))~(4)doped with different concentrations of Mn_(4+)were successfully synthesized by a high-temperature solid-state reaction method. Crystal composition, microstructure, and luminescence properties of samples were characterized by X-ray diffraction, scanning electron microscope, excitation and emission spectra, decay lifetimes and temperature-dependent photoluminescence spectra. The emission spectra exhibited a strong deep-red emission band in the wavelength range of 625–750 nm with a maximum at 678 nm. The optimal doping concentration of Mn_(4+)was about 0.1 mol%. Under 325 nm excitation, the CIE chromaticity coordinates of Ca~(3)Y(AlO)~(3)(BO~(3))~(4):0.1%Mn_(4+)sample were (0.704, 0.296). In addition, the concentration quenching mechanism was dominated by a dipole–dipole interaction for the Mn_(4+)activators. The value of the activation energy E~(a)was calculated to explain thermal quenching.