Emerging Ultraviolet Persistent Luminescent Materials

Abstract

Ultraviolet (UV, 200–400 nm) persistent luminescence (PersL) is an emerging topic of luminescent materials due to their “self‐sustainable” high‐photon‐energy characteristics. Although the family of UV PersL materials is fast‐growing, especially in the past few years, an overview on the current status in terms of material development, mechanism investigation, promising applications, research challenges, future directions, and the correlations of these aspects is absent. Many potential applications of UV PersL have recently been demonstrated and proposed depending on where UV PersL falls in the UVA (315–400 nm), UVB (280–315 nm), or UVC (200–280 nm) range. Hence, here the state‐of‐the‐art UV PersL materials, the theoretical and experimental attempts and explanations of UV PersL mechanisms, and strategies utilized to improve UV PersL performance are summarized. Also their unprecedented application promises spanning “solar‐blind” tagging (“glow‐in‐the‐bright” tagging), persistent disinfection, persistent photocatalysis, and “device‐free” skin phototherapy that are beyond the capabilities of the “glow‐in‐the‐dark” visible and infrared PersL are discussed. Facing challenges in understanding their complicated mechanisms, meeting their high charging requirement, and easing the public concerns, a bright future for UV PersL materials from lab to market is envisaged.

High charge carrier storage capacity and wide range X-rays to infrared photon sensing in LiLuGeO4:Bi3+,Ln3+ (Ln = Pr, Tb, or Dy) for anti-counterfeiting and information storage applications

“…About 86% of the emission spectrum appears in the ultraviolet A (UV-A) spectral range from 315 to 400 nm. 35,43,44 The excitation spectrum monitored at 358 nm gives rise to an excitation band peaked at 233.5 nm and two strong excitation bands peaked at 297 nm and 307.5 nm. Similar to ref.…”

Achieving multicolour and multimodal luminescence in Ca3Al2Ge3O12:Bi3+/Ln3+(Ln = Tb, Eu, Sm, and Dy) persistent phosphors for multiple applications

“…, ultraviolet (UV), X-ray, gamma rays or visible light) has been removed. 1–5 At the other end of the spectrum in the shorter wavelength UV region (200–400 nm), especially UVB persistent phosphors, which exhibit excellent afterglow properties and can be activated by a wide range of available light sources ( e.g. , UV lamps) given the advantage of their excellent invisibility (invisible to the naked eye), UV luminescent materials are promising for a wide range of applications in environmental, biological and medical fields, 6–11 however, for some important new applications (anti-counterfeiting or information storage), this phosphor has not yet been fully explored.…”

“…Persistent luminescent (PersL) materials present the fascinating ability to store excitation energy, a special optical phenomenon in which the material has the ability to emit light for seconds to hours after the excitation source (e.g., ultraviolet (UV), X-ray, gamma rays or visible light) has been removed. [1][2][3][4][5] At the other end of the spectrum in the shorter wavelength UV region (200-400 nm), especially UVB persistent phosphors, which exhibit excellent afterglow properties and can be activated by a wide range of available light sources (e.g., UV lamps) given the advantage of their excellent invisibility (invisible to the naked eye), UV luminescent materials are promising for a wide range of applications in environmental, biological and medical fields, [6][7][8][9][10][11] however, for some important new applications (anti-counterfeiting or information storage), this phosphor has not yet been fully explored. [12][13][14] Counterfeiting phenomena are widespread in all aspects of economics and social life and pose a global security threat to both individuals and society.…”

Long-persistent far-UVC light emission in Pr3+-doped Sr2P2O7 phosphor for microbial sterilization

“…[18][19][20][21] Especially, UVC persistent luminescence is becoming an indispensable complement to conventional UVC light sources. 22,23 For UVC persistent luminescence phosphors, the trivalent praseodymium (Pr 3+ ) ion is considered a promising emitter due to its high-energy 4f5d state and effective 4f5d → 4f interconfigurational transitions. [24][25][26] Moreover, the Stokes shift of the 4f5d → 4f transitions should be less than ∼3000 cm −1 (0.37 eV), 27 raising special requirements for suitable host materials.…”

“…18–21 Especially, UVC persistent luminescence is becoming an indispensable complement to conventional UVC light sources. 22,23…”