Influence of Eu, Dy co-doped strontium aluminate composition on mechanoluminescence intensity

We have investigated the mechanoluminescence (ML) of Eu,Dy co-doped strontium aluminates. The SrAl2O4 and Sr3Al2O6 indicate high ML intensity, which is clearly visible to the naked eye in the air. SrAl2O4:Eu,Dy shows the highest ML intensity and has many filled traps, high quantum efficiency and moderate stiffness. On the other hand, Sr3Al2O6:Eu,Dy does not have many filled traps and high relative quantum efficiency, but Sr3Al2O6:Eu,Dy shows relatively high ML intensity. Sr3Al2O6:Eu,Dy indicates low stiffness. SrAl4O7:Eu,Dy has many filled traps and high relative quantum efficiency, but SrAl4O7:Eu,Dy shows very small ml intensity. SrAl4O7:Eu,Dy indicates high stiffness. This suggests that the stiffness is an important factor for the ML intensity of the Eu,Dy co-doped strontium aluminate system.