X-ray excited (Mg,Ca)F2:Mn2+for persistent luminescence modulation

Due to the unique outer electronic configuration, Mn2+ can emit tunable luminescence over a wide wavelength range, which thus has a broad spectrum of applications in many fields such as lighting and anti-counterfeiting. Although the persistent luminescence of Mn2+ in oxyacid salts has been widely studied, it is, however, rarely mentioned in fluorides, due to the fluorides' wide band gap which cannot be effectively excited by ultraviolet light. Here, we mainly study the persistent luminescence of MgF2:Mn2+ upon excitation of X-ray source. In addition, we also investigate the influence of Ca2+ on the persistent luminescence of MgF2:Mn2+, and success-fully achieve luminescence modulation from orange toward green in the CIE chromaticity coordinates. Finally, we show the potential applications of the persistent luminescence of (Mg,Ca)F2:Mn2+ in terms of dynamic security.