Multicolor persistent luminescence realized by persistent color conversion

Spectral tuning is important for the development of persistent phosphors. Here we introduce a color conversion concept to obtain abundant persistent luminescence spectra in addition to existing methods of exploring new matrix and/or dopants. In this study, CaAl₂O₄:Eu,Nd was chosen as a blue persistent donor phosphor, while Lu₃Al₅O₁₂:Ce and other four commercial phosphors were explored as conversion phosphors to obtain colorful persistent luminescence spectra. Both the persistent donor phosphor and conversion phosphors were embedded into resin, forming ternary composite chips to ensure efficient energy transfer. Continuous color tuning were realized by simply changing the mass ratio of the persistent donor phosphor vs. conversion phosphor. Our work will be significant in indicating other persistent/conversion composite materials or nanostructures with abundant spectral properties.