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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]

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]

Till now, many doped persistent luminescence (PersL) phosphors have been investigated and found various applications in such as bioimaging, photocatalysis and information storage, but introducing PersL emitters into a proper host is mostly complex. In this research, a self‐activated PersL phosphor Ba2Zr2Si3O12 (BZSO) is prepared by solid state reaction. By adding NH4Cl, the self‐activated PersL intensity is evidently enhanced. The trap depths and concentrations are examined by thermoluminescence spectra. Meanwhile, Bi3+ ions are introduced into BZSO and show wide band photoluminescence (PL) from 300 to 600 nm. Moreover, the PL of Bi3+ is tunable under excitation by 265‐350 nm lights. Furthermore, as a proof‐of‐concept design, we designed a patterned quick response (QR) code based on the self‐activated PersL of BZSO, and the information of "South China University of Technology (SCUT)" can be read out by the code scanning technology. Bi3+‐doped BZSO phosphors are suggested to provide potential applications in information storage by its self‐activated PersL, and to excite researchers to study the tunable PL in Bi3+‐doped phosphor. [ABSTRACT FROM AUTHOR]

Persistent luminescence (PersL) materials that can be excited by natural sunlight are in great demand to reduce energy consumption, but the design and development of efficient sunlight-activated PersL phosphor remains a daunting challenge so far. Herein, we report the development of a new kind of sunlight-activated PersL material based on Bi3+-doped Sr 3 Y 2 Ge 3 O 12 (SYGO) phosphor, which exhibits an intense UV–Visible-NIR PersL and possesses a super-long PersL longer than 60 h. This newly developed PersL material can be effectively and repeatedly activated by sunlight radiation in all kinds of weather conditions because of its high response to both direct sunlight and diffuse solar radiation. Owing to the existence of stabilized deep traps with suitable depths, SYGO:Bi3+ also shows excellent photostimulated luminescence (PSL) properties. A series of excitation-time-dependent TL experiments, PL and PersL spectra were systematically studied to reveal the trapping and de-trapping processes of this material. Furthermore, by utilizing the unique PersL and PSL properties, we demonstrate the applications of SYGO:Bi3+ for night-vision signage and optical information storage. Our achievement in the case of Bi3+-doped SYGO phosphor is expected to promote the future development of more excellent sunlight-activated and photostimulated PersL materials towards versatile practical applications. [Display omitted] • Develop a new kind of sunlight-activated persistent luminescence (PersL) material • Discover their ability of being repeatedly excited by sunlight in all weather conditions • This material exhibits outstanding photostimulated luminescence properties. • Unravel the trapping and de-trapping processes and the underlying PersL mechanism • Successfully demonstrate of this material for energy storage applications [ABSTRACT FROM AUTHOR]

In this study, we report the successful synthesis of SrCa 1-δ MgW 1-x O 6 :xMn, δLa3+ (SC 1-δ MW 1-x O:xMn, δLa3+) phosphors using a nonequivalent substitution strategy from the nearly non-luminescent SCMWO:Mn. The as-synthesized (Mn, La3+) co-doped SCMWO phosphors exhibit highly efficient far-red luminescence, which is correlated with the valence transformation of Mn2+ to Mn4+ through La3+ substitution. Besides, the Mn2+ → Mn4+ valence transformation also results in a migration of Mn from the center of [MgO 6 ] to [WO 6 ]. More importantly, it was discovered that the SC 0.81 MW 0.995 O:0.005Mn, 0.19La3+ phosphor exhibited an excellent anti-thermal-quenching performance, with an emission intensity of 107.3 % at 423 K than that at 298 K. This phosphor also showed a high luminous efficiency, with an internal quantum efficiency (IQE) of 50.4 %, and an external quantum efficiency (EQE) of 43.2 %. Additionally, the intense far-red emission peak at 693 nm of SC 0.81 MW 0.993 O:0.007Mn, 0.19La3+ phosphor matches well with the absorption band of phytochrome PFR. These results indicate that the synthesized phosphors may have promising applications not only in plant growth but also in white light-emitting diodes (WLEDs). [Display omitted] • SrCa 1-δ MgW 1-x O 6 :xMn, δLa3+ phosphor was successfully synthesized. • La3+ substitution resulted in highly efficient luminescence of SCMWO:Mn sample. • The influence of La3+ ions on the valence variation and the migration of Mn in SCMWO was studied. • The SrCa 0·81 MgW 0·995 O 6 :0.005Mn, 0.19La3+ phosphor owned an emission intensity of 107.3 % at 423 K than that of 298 K. • The emission of the fabricated deep-red LED device matches well with the absorption of plant. [ABSTRACT FROM AUTHOR]