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Cr3+ doped garnet‐type (A3B2C3O12) near‐infrared (NIR) phosphors is a desirable research hotspot due to their prospective night vision, bioimaging, and plant growth utilizations. Meanwhile, the origin of multisite broad emission is yet a controversial topic. To resolve the trouble, verifying accurately the multiple Cr3+ occupancy sites is a key. Furthermore, it is an urgent need for improving the external quantum efficiency and luminescent thermostability. Herein, in Y3Sc2Al3O12 (YSAO), advanced electron microscopy technique is employed to directly confirm that the obtained broadband NIR emission originates from Cr3+ in [ScO6] octahedral and [YO8] dodecahedral sites. The optimal YSAO:5%Cr3+ sample exhibits high quantum efficiency (IQE/EQE = 74/31%) and near‐zero thermal quenching (97%@423 K and 92%@473 K). The theoretical calculations and experimental proofs reveal that YSAO possesses high structural rigidity and wide bandgap, which is responsible for the extremely thermostable luminescence. The high‐power YSAO:5%Cr3+‐converted NIR LED device shows promising multifunctional applications. This work not only provides an efficient NIR broadband phosphor with near‐zero thermal quenching, but also provides an effective determination method for the multiple emitting centers of phosphor materials. [ABSTRACT FROM AUTHOR]

Our density functional theory calculations show that silicon doping in g-CN (SiC3N3) can improve the electrochemical performance of g-CN as an anode of alkali metal-ion batteries and solve the problems of too high adsorption ability and migration energy barrier commonly found in porous carbon nitride. The stability of SiC3N3 was verified by molecular dynamics simulations and phonon spectroscopy. Elastic constant calculations revealed that the Si doping in g-CN can improve its mechanical properties. Specifically, Li/Na/K has a suitable adsorption capability (−0.71/−0.52/−0.98 eV) and a lower migration barrier (0.73/0.43/0.21 eV) on SiC3N3, where the barrier of a single Li-ion is the lowest among the doped porous carbon nitride materials studied so far. Moreover, SiC3N3 exhibits a high theoretical capacity (253/1512/1512 mA h g−1) and a low open-circuit voltage (0.48/0.18/0.31 V) for Li/Na/K ion batteries. Compared with B-doped g-CN previously studied, Si doping can more effectively improve the electronic conductivity of g-CN owing to greater charge transfer between Si and g-CN; the migration energy barrier of alkali metal ions on SiC3N3 is reduced more significantly due to its puckered structure instead of a planar structure; and the capacity of SiC3N3 is nearly doubled for alkali metal ion batteries because it has more feasible adsorption sites for alkali metals. These results suggest that Si-doped g-CN can be a universal anode material for alkali metal ion batteries. [ABSTRACT FROM AUTHOR]

Eu3+‐activated red‐emitting inorganic phosphors have been favored highly for their classical 5D0→7FJ (J = 0, 1, 2, 3, 4) emissions. However, the fatal drawbacks of poor luminous efficacy and weak 5D0→7F4 transition persist, resulting in the ongoing challenge of achieving far‐red emission. This research reports series of highly efficient far‐red phosphors LnTeBO5 (Ln = La3+, Y3+, Gd3+):Eu3+ with anomalously strong 5D0→7F4 transition, resulting from the distorted square antiprism [Ln/EuO8]. Both the luminous efficacy and thermal stability can be greatly enhanced via the simple composition variation. [Ln/EuO8] square antiprism‐triggered 5D0→7F2,4 transitions are elucidated in depth, acquiring ultra‐high luminous efficacy (IQE = 95%, EQE = 40%, and AE = 42%) and near‐zero thermal quenching (99%@150°C and 98%@200°C). Subsequently, the versatile utilizations in indoor lighting, plant growth lighting, and security ink are illustrated. This finding establishes a deep understanding for constructing high‐quality far‐red phosphors via the Eu3+‐centered structural units of square antiprism. [ABSTRACT FROM AUTHOR]

Our density functional theory calculations show that silicon doping in g-CN (SiC 3 N 3 ) can improve the electrochemical performance of g-CN as an anode of alkali metal-ion batteries and solve the problems of too high adsorption ability and migration energy barrier commonly found in porous carbon nitride. The stability of SiC 3 N 3 was verified by molecular dynamics simulations and phonon spectroscopy. Elastic constant calculations revealed that the Si doping in g-CN can improve its mechanical properties. Specifically, Li/Na/K has a suitable adsorption capability (-0.71/-0.52/-0.98 eV) and a lower migration barrier (0.73/0.43/0.21 eV) on SiC 3 N 3 , where the barrier of a single Li-ion is the lowest among the doped porous carbon nitride materials studied so far. Moreover, SiC 3 N 3 exhibits a high theoretical capacity (253/1512/1512 mA h g -1 ) and a low open-circuit voltage (0.48/0.18/0.31 V) for Li/Na/K ion batteries. Compared with B-doped g-CN previously studied, Si doping can more effectively improve the electronic conductivity of g-CN owing to greater charge transfer between Si and g-CN; the migration energy barrier of alkali metal ions on SiC 3 N 3 is reduced more significantly due to its puckered structure instead of a planar structure; and the capacity of SiC 3 N 3 is nearly doubled for alkali metal ion batteries because it has more feasible adsorption sites for alkali metals. These results suggest that Si-doped g-CN can be a universal anode material for alkali metal ion batteries.