Linear charging-discharging of an ultralong UVA persistent phosphor for advanced optical data storage and wide-wavelength-range detector

Ultraviolet persistent luminescence (UV PersL) phosphor is currently gaining considerable attention due to its promising potential for widespread advanced applications. However, the linear manipulation of electron charging-discharging and the prolongation of persistent time remains a huge challenge. Here, we report a novel Bi3+ doped Mg2GeO4 UVA PersL phosphor via a nonequivalent substitution strategy. The UVA PersL performance of Mg2GeO4:Bi3+ is significantly improved by introducing Li+ ions, yielding a superior UVA PersL property with afterglow lasting time beyond 100 h. The trap distribution management and the captured electron motion dy-namics are revealed by the thermoluminescence technique under various external stimuli. Moreover, UVA PersL can be repeatedly rejuvenated by NIR and blue LED stimulation owing to the optically stimulated electrons from different depth traps to shallow traps. Due to the invisibility of UVA light, barcode information stored on the phosphor film can be read by NIR light and then erased by blue light, exhibiting the potential application in optical data storage with good concealment and security. Most remarkable is the electron charging-discharging linear functions of the irradiated power of UV, and blue and NIR light which was never reported, providing a feasible approach for optical power detection in a wide-wavelength-range. This work not only offers a guideline to develop novel high-performance UV PersL materials but also provides a route to effectively manipulate the electrons in the traps toward applications in advanced optical information storage and wide-wavelength-range light detection.

Automated summary

This study reports a novel Bi3+ doped Mg2GeO4 UVA PersL phosphor with improved persistent luminescence performance. By introducing Li+ ions, the UVA PersL property is significantly enhanced, enabling afterglow lasting beyond 100 hours. The findings offer potential applications in optical data storage and wide-wavelength-range light detection.