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Herein, ultraviolet B (UVB) persistent luminescence phosphors containing SrAl 12 O 19 : Ce3+, Sc3+ nanoparticles were reported. Thermoluminescence (TL) spectrum analysis reveals that the shallow trap induced by Sc3+ co-doping plays an important role in photoluminescence persistent luminescence (PersL) development, while the deep trap dominates the generation of optical stimulated luminescence (OSL). Owing the appearance of deep trap, the OSL is observed under light (700 nm - 900 nm) excitation. UVB luminescence exerts good bactericidal effects on pathogenic bacteria involved in the process of food spoilage. Thus, the smart window with SrAl 12 O 19 : Ce3+, Sc3+/PDMS produces UVB PersL to efficiently inactivate Escherichia coli and Staphylococcus aureus. In addition, the presence of the smart window delays the critical point of pork decay, and greatly reduces the time of pork spoilage. It maximizes the convenience of eradicating bacteria and preserving food, thus offering a fresh perspective on the use of UV light for food sterilization and preservation. • PL, PersL and OSL in the UVB range are demonstrated in SrAl 12 O 19 doped with Ce3+. • The shallow trap induced by the Sc3+ co-doping plays an important role in PersL. • The deep trap dominates the generation of OSL. • Smart window can inactivate Escherichia coli and Staphylococcus aureus. • This smart windows dramatically delay pork spoilage. [ABSTRACT FROM AUTHOR]

The persistent phosphor Y 3 Ga 5 O 12 : 0.5%Cr3+ (YGG:C) and Y 3 Ga 5 O 12 : 0.5%Cr3+, 0.5%Si4+ (YGG: CS) were synthesized by traditional solid-state reaction. Y 3 Ga 5 O 12 was employed as a host to take advantage of its abundant intrinsic traps. Moreover, Si4+ dopant was introduced to precisely tailor the trap distribution so that the initial persistent brightness of YGG: CS is around 7 times higher than that of YGG: C. The photo-stimulated traps were firstly found in YGG: CS, and the effective number of photo-stimulation was confirmed to be several hundreds. The broad emission band (650–950 nm) of YGG: CS and useful stimulated source (655 nm) are all located in the biological window (650–1350 nm). In this work, pork tissue imaging experiments were performed by means of the hundreds of hours persistent luminescence and hundreds of times photo-stimulated property of YGG: CS. Image 1 • The persistent property of the YGG: Cr3+ was improved for more than sevenfold. • Afterglow of YGG: Cr3+, Si4+ reappear through low-energy photo-stimulation. • The efficiency photo-stimulation process can be repeated hundreds of times. • Photo-stimulation dependence YGG: Cr3+, Si4+ showed great bio-imaging property. [ABSTRACT FROM AUTHOR]

Abstract A dual-emission long persistent luminescence phosphor SrZrO 3 : Yb3+ is synthesized through a conventional high-temperature solid-state reaction method. A combined experiment and first-principles methods are carried out to study the inner link between the electronic structures and spectroscopic characteristics of SrZrO 3 : Yb3+ phosphor. The calculation shows that the incorporation of Yb3+ ions into SrZrO 3 lattice can be done through substituting Yb3+ ions for Sr site. It is found that vacancy defects of SrZrO 3 : Yb3+ system easily produce around the doping positions. Especially, the oxygen vacancies, which are deduced as the intrinsic vacancy defect, are responsible for the persistent luminescence in SrZrO 3 : Yb3+ phosphor. The persistent luminescence of SrZrO 3 : Yb3+ consists of two parts: near-ultraviolet persistence originate from self-trapped excitons of host, and near-infrared one stems from 2F 5/2 → 2F 7/2 transitions of Yb3+. The photoluminescence and persistent performance are studied as function of the concentration of Yb3+ ions. The optimal concentration of Yb3+ ions for the photoluminescence emission and long persistent luminescence are both approximately 2.5%. The long persistent luminescence mechanism for SrZrO 3 :Yb3+ is illuminated on the basis of photoluminescence and first-principle calculation results. Highlights • SrZrO 3 : Yb3+ presents a dual-emission (NUV and NIR) long persistent luminescence. • Oxygen vacancies in SrZrO 3 :Yb3+ play an important role in the persistent luminescence. • The PL and calculation results confirm the persistent mechanism of SrZrO 3 :Yb3+. [ABSTRACT FROM AUTHOR]