Green mechanoluminescence of Ca2MgSi2O7 : Eu and Ca2MgSi2O7 : Eu,Dy

We discovered that Ca2MgSi2O7:Eu,Dy phosphor emits green light under the application of a mechanical stress, a phenomenon known as mechanoluminescence (ML), and this green ML emission can be seen by the naked eye when pressing the sample. The ML showed a similar spectrum as photoluminescence (PL), which indicated that ML is emitted from the same center of Eu2+ ions as PL. Furthermore, the addition of Dy3+ increases the green ML intensity of Ca2MgSi2O7:Eu,Dy considerably - approximately two orders of magnitude greater than that of Ca2MgSi2O7:Eu. The formation of many shallow traps (Dy4+) may be responsible for this enhancement. (c) 2007 The Electrochemical Society.