Photoluminescence properties of (Sr1−xCax)1−yZrO3:yEu3+ phosphors for near-ultraviolet excited LEDs

Red-emitting (Sr1−xCax)1−yZrO3:yEu3+ (0≤x≤1.0 and 0.01≤y≤0.1) phosphors are synthesized by a modified solid-state reaction. The crystal structure and photoluminescence properties of the (Sr1−xCax)1−yZrO3:yEu3+ are studied, depending on Ca2+ and Eu3+ contents. The emission peak (614 nm) from the 5D0→7F2 transition is much stronger than that (592 nm) from the 5D0→7F1 transition, indicating efficient red emission. The substitution of Ca2+ for Sr2+ in Sr0.95ZrO3:0.05Eu3+ greatly enhances the excitation and emission intensities. The most efficient red emission is obtained for the Ca0.95ZrO3:0.05Eu phosphor. The Ca0.95ZrO3:0.05Eu3+ phosphor is a strong candidate as a red component for phosphor-converted white LEDs.