Gd³⁺-activated narrowband ultraviolet-B persistent luminescence through persistent energy transfer

Area of Science:

• Materials Science
• Luminescence
• Solid-State Chemistry

Background:

• Persistent luminescence materials store and emit light after excitation.
• Gadolinium (Gd3+) luminescence is typically in the UV range.
• Developing narrowband ultraviolet-B (NB-UVB) persistent phosphors is challenging.

Purpose of the Study:

• To realize Gd3+ persistent luminescence in the NB-UVB spectral region (310-313 nm).
• To establish a general design concept for Gd3+-activated NB-UVB persistent phosphors.
• To explore potential applications in dermatological therapy.

Main Methods:

• Utilizing persistent energy transfer from sensitizers (Pr3+, Pb2+, or Bi3+) to Gd3+ ions.
• Synthesizing and characterizing novel Gd3+-activated persistent phosphors.
• Investigating the spectral properties and luminescence decay times.

Main Results:

• Successful realization of Gd3+ NB-UVB persistent luminescence via efficient energy transfer.
• Discovery of ten new Gd3+ NB-UVB persistent phosphors and five UV-B persistent phosphors.
• Observed NB-UVB afterglow lasting over 10 hours.

Conclusions:

• A general design strategy for Gd3+-activated NB-UVB phosphors was proposed and validated.
• The developed phosphors efficiently emit in the NB-UVB range with extended afterglow.
• These materials show promise as self-sustained NB-UVB radiation sources for phototherapy.