A Single‐Phased Sr 1− y ‐3 x /2 Al 2 Si 2 O 8 : x Ce 3+ , y Mn 2+ with Efficient Energy Transfer as a Potential Phosphor for White‐Light‐Emitting Diodes

A series of Ce 3+ ‐ and Mn 2+ ‐(co‐)activated SrAl 2 Si 2 O 8 phosphors have been prepared at 1350°C under a reducing atmosphere and their photoluminescence properties have been studied as a function of the (co‐)dopant ions concentrations. We have discovered that energy transfer (ET) not only from Ce 3+ to Mn 2+ but also from “defects” to Mn 2+ by the facts that there is existing significant overlap between the emission spectrum of Ce 3+ (“defects”) and the excitation spectrum of Mn 2+ . The source of the “defects” in the host lattice is originated from the different charge substitution between Ce 3+ and Sr 2+ . By adopting the principle of ET, the material SrAl 2 Si 2 O 8 : Ce , Mn can act as a phosphor for white‐light ultraviolet light‐emitting diodes ( UV ‐ LED s) by tuning of the dopants contents.