Studies on the luminescence properties of cerium co-doping on Ca₂ MgSi₂ O₇ :Eu²⁺ phosphor by solid-state reaction...

Ca₂ MgSi₂ O₇ :Ce³⁺ , Ca₂ MgSi₂ O₇ :Eu²⁺ and Ca₂ MgSi₂ O₇ :Eu²⁺ ,Ce³⁺ phosphors were prepared using the solid-state reaction method. The crystal structures of the sintered phosphors were of melilite type, which has a tetragonal crystallography. The chemical compositions of the sintered phosphors was confirmed by energy dispersive X-ray spectroscopy. The different thermoluminescence kinetic parameters [activation energy (E), frequency factor (s) and order of the kinetics (b)] of these phosphors were evaluated and compared using the peak shape method. Under ultraviolet excitation, the emission spectra of both Ca₂ MgSi₂ O₇ :Eu²⁺ and Ca₂ MgSi₂ O₇ :Eu²⁺ ,Ce³⁺ phosphors were composed of a broad emission band peaking at 530 nm. When the Ca₂ MgSi₂ O₇ :Eu²⁺ phosphor is co-doped with Ce³⁺ ions, photoluminescence, afterglow and mechanoluminescence intensity was strongly enhanced. Ca₂ MgSi₂ O₇ :Eu²⁺ showed some afterglow with a short persist time. On incorporation of Ce³⁺ , efficient energy transfer from Ce³⁺ to Eu²⁺ was found and the emission intensity of Eu²⁺ was enhanced. The mechanoluminescence intensities of Ca₂ MgSi₂ O₇ :Ce³⁺ , Ca₂ MgSi₂ O₇ :Eu²⁺ and Ca₂ MgSi₂ O₇ :Eu²⁺ ,Ce³⁺ phosphors increased proportionally increased with the increase in impact velocity, which suggests that these phosphors can be used as sensors to detect stress in an object.