The near-infrared (NIR) light source is desirable for realtime nondestructive examination applications, which include the analysis of foodstuffs, health monitoring, iris recognition, and infrared cameras. The emission spectra of such an infrared light source should also be as broad as possible for effective performance, in view of the fact that the broad absorption and reflection of light by the organic elements present in foodstuffs and human health fall in the blue and NIR regions of the electromagnetic spectrum, respectively. In this letter, a blue light-emitting diode (LED) excitable super broadband NIR phosphor light source is developed with a high fwhm of 330 nm and radiant flux of 18.2 mW for the first time. The observation of superbroad-band luminescence from two distinct luminescence centers is studied and evidenced by electron paramagnetic resonance, X-ray absorption near-edge structure, steady-state luminescence, and timeresolved luminescence at ambient and high-pressure environments. Finally, the luminescence mechanism is discussed with the relevant configurational coordinate diagrams.

Inorganic solid lithium ion conductors are potential candidates as replacement for conventional organic electrolytes for safety concerns. However, achieving a Li-ion conductivity comparable to that in existing liquid electrolytes (>1 mS cm–1) remains a challenge in solid-state electrolytes. One of the approaches for achieving a desirable conductivity is doping of various elements into the lattice framework. Our discussion on the structure and conductivity of crystalline Li-ion conductors includes description of NAtrium Super Ionic CONductor (NASICON)-type conductors, garnet-type conductors, perovskite-type conductors, and Lithium Super Ionic CONductor (LISICON)-type conductors. Moreover, we discuss various strategies currently used to enhance ionic conductivity, including theoretical approaches, ultimately optimizing the electrolyte/electrode interface and improving cell performance.

Portable near-infrared (NIR) light sources are in high demand for applications in spectroscopy, night vision, bioimaging, and many others. Typical phosphor designs feature isolated Cr 3+ ion centers, and it is challenging to design broadband NIR phosphors based on Cr 3+ −Cr 3+ pairs. Here, we explore the solidsolution series SrAl 11.88−x Ga x O 19 :0.12Cr 3+ (x = 0, 2, 4, 6, 8, 10, and 12) as phosphors featuring Cr 3+ −Cr 3+ pairs and evaluate structure−property relations within the series. We establish the incorporation of Ga within the magentoplumbite-type structure at five distinct crystallographic sites and evaluate the effect of this incorporation on the Cr 3+ −Cr 3+ ion pair proximity. Electron paramagnetic measurements reveal the presence of both isolated Cr 3+ and Cr 3+ − Cr 3+ pairs, resulting in NIR luminescence at approximately 650−1050 nm. Unexpectedly, the origin of broadband NIR luminescence with a peak within the range 740−820 nm is related to the Cr 3+ −Cr 3+ ion pair. We demonstrate the application of the SrAl 5.88 Ga 6 O 19 :0.12Cr 3+ phosphor, which possesses an internal quantum efficiency of ∼85%, a radiant flux of ∼95 mW, and zero thermal quenching up to 500 K. This work provides a further understanding of spectral shifts in phosphor solid solutions and in particular the application of the magentoplumbites as promising next-generation NIR phosphor host systems.

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An efficient multi-doping strategy to enhance Li-ion conductivity in the garnet-An efficient multi-doping strategy to enhance Li-ion conductivity in the garnettype solid electrolyte Li7La3Zr2O12 type solid electrolyte Li7La3Zr2O12 Abstract Abstract Lithium-ion (Li + ) batteries suffer from problems caused by the chemical instability of their organic electrolytes. Solid-state electrolytes that exhibit high ionic conductivities and are stable to lithium metal are potential replacements for flammable organic electrolytes. Garnet-type Li 7 La 3 Zr 2 O 12 is a promising solid-state electrolyte for next-generation solid-state Li batteries. In this study, we prepared mono-, dual-, and ternary-doped lithium (Li) garnets by doping tantalum (Ta), tantalum-barium (Ta-Ba), and tantalum-barium-gallium (Ta-Ba-Ga) ions, along with an undoped Li 7 La 3 Zr 2 O 12 (LLZO) cubic garnet electrolyte, using a conventional solid-state reaction method. The effect of multi-ion doping on the Li + dynamics in the garnet-type LLZO was studied by combining joint Rietveld refinement against X-ray diffraction and high-resolution neutron powder diffraction analyses with the results of Raman spectroscopy, scanning electron microscopy, energy-dispersive X-ray spectroscopy, and multinuclear magic angle spinning nuclear magnetic resonance. Our results revealed that Li + occupancy in the tetrahedrally coordinated site (24d) increased with increased multi-ion doping in LLZO, whereas Li + occupancy in the octahedrally coordinated site (96h) remained constant. Among the investigated compounds, the ternary-doped garnet structure Li 6.65 Ga 0.05 La 2.95 Ba 0.05 Zr 1.75 Ta 0.25 O 12 (LGLBZTO) exhibited the highest total ionic conductivity of 0.72 and 1.24 mS cm -1 at room temperature and 60 °C, respectively. Overall, our findings revealed that the dense microstructure and increased Li + occupancy in the tetrahedral-24d Li1 site played a key role in achieving the maximum room-temperature Li-ion conductivity in the ternary-doped LGLBZTO garnet, and that the prepared ternary-doped LGLBZTO was a potential solid electrolyte for Li-ion batteries without polymer adhesion. Disciplines DisciplinesEngineering | Physical Sciences and Mathematics ABSTRACT Lithium-ion (Li + ) batteries suffer from problems caused by the chemical instability of their organic electrolyte. Solid-state electrolytes that exhibit high ionic conductivities and stable to lithium metal are potential replacements for flammable organic electrolytes.Garnet-type Li7La3Zr2O12 is a promising solid-state electrolyte for next-generation solidstate Li batteries. In this study, we prepared mono-, dual-, and ternary-doped lithium (Li)