Orange emission enhancement by energy transfer in Sr3Al2O5Cl2:Ce3+, Eu2+ phosphor for solid-state lighting

Orange-emissive Ce3+/Eu2+ co-doped Sr3Al2O5Cl2 phosphors were synthesized by a solid-state reaction. The large overlap between the emission spectrum of blue Sr3Al2O5Cl2:Ce3+ and the excitation spectrum of orange Sr3Al2O5Cl2:Eu2+, and the shortening trend in lifetime of Ce3+ donors with increasing Eu2+ concentration in Sr3Al2O5Cl2:Ce3+, Eu2+ provide the strong evidence of energy transfer from Ce3+ to Eu2+ ions. It supports that the orange emission intensity of the optimal co-doped phosphor is 1.5 times stronger than that of single Eu2+-doped one. The Sr3Al2O5Cl2:Ce3+, Eu2+ phosphor is a promising orange-emitting phosphor for warm-white-light-emitting diode because of its effective excitation in the near ultraviolet range.