High color purity red phosphors of Ca 1À3/2x Eu x TiO 3 and Ca 1À2x Eu x Li x TiO 3 (0 < x 0.3) are synthesized via a solidstate reaction method. The red emission photoluminescence intensity and color purity are enhanced by the incorporation of Li + into CaTiO 3 :Eu 3+ . The Li + doping increases the emission probability from 5 D 0 state, increases photoluminescence intensity by 1.6 times, increases color purity to 92.1%, and shortens the decay time. With increasing Eu 3+ and Li + content, the color coordinates approach the ideal red chromaticity values, coming closer than commercial Y 2 O 2 S:Eu 3+ red phosphor.

Ca3Sc2Si3O12:Ce3+ (CSS:Ce) green phosphors used for white light‐emitting diodes (LEDs) are synthesized and codoped with Al3+ via a solid‐state reaction method. The crystal structure and vibrational modes are analyzed by X‐ray diffraction, Fourier transform infrared spectroscopy, and Raman scattering spectroscopy. The energy transfer behavior and optical performance are characterized by photoluminescence and excitation spectra, quantum efficiency, and time‐resolved photoluminescence. The incorporation of Al3+ into CSS:Ce can inhibit the formation of the impurity phases Sc2O3 and CeO2, improve crystallinity, and enhance the photoluminescence intensity as well as quantum efficiency. The substitution of Sc3+ with Al3+ increased the crystal field splitting of Ce3+ and resulted in the red shift of photoluminescence. The results show that Ca3Sc2−xAlxSi3O12:Ce3+ has high quantum efficiency, making it a promising green phosphor that can be collocated with a commercial 450 nm blue LED and a red phosphor for solid‐state lighting applications.

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