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With the fast‐growing amount of data, the state‐of‐the‐art optical data storage has become a front‐runner in the competing data storage technologies. However, two‐dimensional (2D) spatial resolution in the conventional optical data storage media has almost reached the limit. Herein, LiGa5O8:Cr3+ nanoparticles (NCs) precipitated in situ from a transparent medium are prepared. The transparent LiGa5O8:Cr3+ glass ceramics show excellent deep‐trap carriers storage ability under blue light irradiation and can realize the bit‐by‐bit optical data in 3D space for write‐in and read‐out in a photon trapping/detrapping mode. Moreover, this optical storage mechanism is also extended to 4D by realizing temperature optical encryption. Notably, the written information can still be clearly displayed even after being recorded for 200 days. This work enables 4D high‐precision storage of information and provides new insights into the design and fabrication of next‐generation storage materials. [ABSTRACT FROM AUTHOR]

Broadband near‐infrared (NIR) phosphors have recently received considerable attention in spectroscopy technology fields, but designing inexpensive, emission peaks centered above 800 nm, and multimodal broadband NIR luminescence material still remains a great challenge. Here, by selecting stannate compound Mg2SnO4 (MSO) as the host, a kind of broadband NIR phosphor MSO:Cr3+ with multimode luminescence properties is reported. The designed material exhibits an emission peaking at 800 nm and a full‐width at half maximum of 180 nm (≈2730 cm−1). The site occupation of Cr3+ in MSO is unraveled by density functional theory calculation. The constructed NIR light‐emitting device based on MSO:Cr3+ displays a high NIR output power of 187.19 mW@100 mA and remarkable photoelectric efficiency of 13.67%, and its multifunctional applications in information encryption, non‐destructive detection, and so on are also demonstrated. Additionally, through defect site reconstruction, MSO:Cr3+ presents superior broadband NIR persistent luminescence (PersL) properties with PersL duration time longer than 50 h. This work provides a feasible strategy to develop intelligent optical material integrated with multimodal luminescence through low‐cost stannate compounds as the host toward versatile applications such as non‐destructive detection and bioimaging. [ABSTRACT FROM AUTHOR]

Luminous properties play an essential role in phosphor-converted white light-emitting diodes for high-quality illumination, where the self-reducing behavior of doped activators and their excellent thermal stability have received significant attention. Here, we prepared NaY9Si6O26:Mn2+ red phosphors by a high-temperature solid-state reaction method, which achieved self-reduction of Mn4+ → Mn2+ and excellent thermal stability (luminous intensity at 420 K is 98% of that at room temperature) under ambient conditions. First-principles calculations and X-ray photoelectron spectroscopy elucidated a self-reduction mechanism from Mn4+ to Mn2+. The defect types were calculated in conjunction with thermoluminescence, verifying that the low thermal quenching properties originated from the transfer of electrons from the defect energy level to the Mn2+ excited state center induced by the cationic vacancy defect, which suppressed the luminescence loss from thermal quenching. In this work, the effect of defects on luminescence properties is highlighted and the further exploration of defect control is stimulated, opening up a new avenue for new types of highly thermally stable materials. [ABSTRACT FROM AUTHOR]

Spinel configuration is a kind of broadly considered host candidate when designing persistent luminescence (PersL) materials due to the easy generation of vacancies and anti‐site defects. Here, a new strategy of defect enrichment for the activation of PersL is proposed, and in contrast to the spinel configuration, it is demonstrated that the crystal structure of near inverse spinel ensures more numerous defects to activate the near‐infrared (NIR) PersL of Fe3+. Fe3+‐doped MgGa2O4 displays the PersL band in the range of 600 to 900 nm and possesses a super‐long PersL duration time >15 h. The optical analysis and the calculation of density functional theory unravel that the near inverse spinel structure can lower the carrier transfer barriers to accelerate the formation of carrier trap states within the bandgap. Therefore, more numerous defects in this structure may participate in the trapping and de‐trapping process by comparison with the normal spinel configuration. These findings are expected to accelerate the development of new PersL materials through Fe3+ doping toward versatile biological applications in NIR window. [ABSTRACT FROM AUTHOR]

Spinel configuration is a kind of broadly considered host candidate when designing persistent luminescence (PersL) materials due to the easy generation of vacancies and anti‐site defects. Here, a new strategy of defect enrichment for the activation of PersL is proposed, and in contrast to the spinel configuration, it is demonstrated that the crystal structure of near inverse spinel ensures more numerous defects to activate the near‐infrared (NIR) PersL of Fe3+. Fe3+‐doped MgGa2O4 displays the PersL band in the range of 600 to 900 nm and possesses a super‐long PersL duration time >15 h. The optical analysis and the calculation of density functional theory unravel that the near inverse spinel structure can lower the carrier transfer barriers to accelerate the formation of carrier trap states within the bandgap. Therefore, more numerous defects in this structure may participate in the trapping and de‐trapping process by comparison with the normal spinel configuration. These findings are expected to accelerate the development of new PersL materials through Fe3+ doping toward versatile biological applications in NIR window. [ABSTRACT FROM AUTHOR]