Studies on up-conversion charging of persistent phosphors are of great academic and practical significance. To date, up-conversion charging designs have been achieved in Cr3+, Mn2+ and Pr3+-activated phosphors. We herein...

Ultraviolet‐C illumination may provide a promising solution for the disinfection technology, and thus the development of novel type of ultraviolet‐C light sources is continuously expected. Herein, a conceptual design of ultraviolet‐C light source based on up‐conversion luminescence of phosphor material is introduced. Accordingly, a composite film is prepared using YBO3:Pr3+ phosphor and a transmissive remote phosphor‐converted light source is built by combing the phosphor film with a 447 nm laser. Spectral measurements show that the phosphor‐converted design emits ultraviolet‐C light peaking at 263 and 274 nm with tunable emission intensities. Moreover, ultraviolet imaging demonstration implies that the present design has a potential to serve as an ultraviolet‐C germicidal light source for surface decontamination.

As an emerging approach to charge storage phosphors, upconversion charging (UCC) is attracting increased attention owing to its fundamental and practical perspectives. Despite the potential, further development of the UCC technology is restricted by the limited types of excitation light sources. Here, we use a white flashlight as excitation to investigate the UCC performance of storage phosphors. We demonstrate, as an example, that a Y3Al2Ga3O12:Pr3+ phosphor exhibits long-lasting emissions in the ultraviolet and visible regions after intense illumination from the flashlight. Thermoluminescence investigations reveal that both excited-state absorption and energy-transfer upconversion are involved in the UCC process. Based on the luminescence performance of the white-light charged phosphor, a conceptual thermometry approach is introduced, which can remotely sense the local temperature by monitoring the afterglow intensity ratio. Considering the wide use of flashlight, such a white-light excitability and the associated glow emission may potentially revolutionize the way to utilize storage phosphors.

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