Tuning of red-emitting luminescence through host-sensitized luminescence effect in Eu^sup 3+^ doped Sr^sub 1−x^Ca^sub x^ZnO^sub 2^ phosphors

A series of Sr1−xCaxZnO2:0.02 Eu3+ phosphors have been prepared by solid-state method. The effects of Ca2+ ions on luminescent properties of SrZnO2:0.02 Eu3+ have been systematically investigated by X-ray diffraction (XRD) patterns, the photoluminescence excitation and emission spectra, and International Commission on Illumination (CIE) chromaticity diagram. The red-emitting of Eu3+ doped Sr1−xCaxZnO2 phosphors can be tuned based on the host-sensitized luminescence effect, in which the maximum emission intensity and 90.05% color purity at 396 nm excitation, a broad emission band ranging from 475 to 800 nm at 374 nm excitation have been achieved in the Sr0.85Ca0.15ZnO2:0.02 Eu3+ sample, which demonstrate the occurrence of energy transfer from host to Eu3+ ions. Therefore, Eu3+ doped Sr1−xCaxZnO2 phosphors will become a promising candidate as a new single-host red-emitting phosphor for white LEDs applications.