Luminescence and Energy Transfer of Eu- and Mn-Coactivated CaAl 2 Si 2 O 8 as a Potential Phosphor for White-Light UVLED

A series of Eu 2+ – and Mn 2+ -coactivated CaAl 2 Si 2 O 8 phosphors have been synthesized at 1400 °C under a reduced atmosphere and their luminescence properties have been investigated as a function of activator and coactivator concentrations. We have discovered that energy transfers from Eu 2+ to Mn 2+ by directly observing significant overlap of the excitation spectrum of Mn 2+ and the emission spectrum of Eu 2+ as well as the systematic relative decline and growth of emission bands of Eu 2+ and Mn 2+, respectively. The critical distance and average separation of Eu 2+ and Mn 2+ have also been calculated. By utilizing the principle of energy transfer, we have also demonstrated that with appropriate tuning of activator content CaAl 2 Si 2 O 8:Eu 2+,Mn 2+ phosphors exhibit great potential to act as a phosphor for white-light ultraviolet light-emitting diodes (UVLEDs).