Luminescence and energy transfer of Eu- and Mn-coactivated CaAl2Si2O8 as a potential phosphor for white-light UVLED

Abstract

A series of Eu2+- and Mn2+-coactivated CaAl2Si2O8 phosphors have been synthesized at 1400 degrees 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 Eu2+ to Mn2+ by directly observing significant overlap of the excitation spectrum of Mn2+ and the emission spectrum of Eu2+ as well as the systematic relative decline and growth of emission bands of Eu2+ and Mn2+, respectively. The critical distance and average separation of Eu2+ and Mn2+ have also been calculated. By utilizing the principle of energy transfer, we have also demonstrated that with appropriate tuning of activator content CaAl2Si2O8:Eu2+ Mn2+ phosphors exhibit great potential to act as a phosphor for white-light ultraviolet light-emitting diodes (UVLEDs).