Persistent luminescence (PersL) has been attracting substantial
attention in diverse frontier applications such as optical information
security and in vivo bioimaging. However, most of the reported PersL
emissions are based on the dopants instead of the host matrix, which
also plays an important role. In addition, there are few works on
the PersL-based multifunctional nanoplatform in nanosized materials.
Here, we report a class of novel nanostructure designs with PersL,
upconversion, and down-shifting luminescence to realize the fine-tuning
of emission colors under different excitation modes including steady-state
irradiation, time-gating, and PersL generation. Blue, orange, and
green emissions were easily achieved in such a single nanoparticle
under suitable excitation modes. Moreover, the physical origin of
the PersL of the CaF2 matrix was discussed by simulating
the energy band structure with CaxFy defects. Our results provide new opportunities
for the design of a new class of multifunctional materials, showing
great promise in the field of information encryption security and
multilevel anticounterfeiting