posted on 2022-12-09, 02:03authored byYi Zhang, Yanjie Liang, Xihui Shan, Dongxun Chen, Shihai Miao, Ruiqi Shi, Fei Xie, Weili Wang
Persistent phosphors emitting in
the narrowband ultraviolet-B
(NB-UVB)
spectral region have aroused significant interest, owing to their
special self-illuminating feature in realizing many advanced technological
applications under excitation-free conditions, such as dermatological
therapy and invisible optical tagging. Here, we focus our discussion
on a new Gd3+-doped persistent phosphor, Sr2P2O7:Gd3+, which exhibits long-lasting
NB-UVB persistent luminescence peaking at 312 nm for more than 24
h after charging by an X-ray beam. The NB-UVB light emission from
the charged Sr2P2O7:Gd3+ phosphor can be clearly detected by a UVB camera in bright indoor
environment. More importantly, the enhancement of NB-UVB afterglow
intensity and decay time can be observed under continuous photostimulation
of polychromic indoor ambient light. Furthermore, applying charged
Sr2P2O7:Gd3+ phosphors
as invisible optical taggants, clear and interference-free recognition
of the encrypted message and location of different objects have been
realized due to the lack of UVB light in bright indoor environment.
The as-prepared Sr2P2O7:Gd3+ persistent phosphor is expected to offer new directional solutions
for the development and application of ultraviolet luminescence technology.