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Transition metal ions, such as Cr3+, Fe3+, and Ni2+, are widely recognized activators for efficient broadband near‐infrared (NIR) phosphors. However, the potential of Mn2+ ions as NIR‐emitting activators is relatively overlooked due to their typically narrowband emission in the visible spectral region and relatively weak absorption. Herein, a heavy Mn2+‐doped Zn1‐xAl2O4: xMn2+ (ZAO: xMn2+) phosphor is presented that exhibits a single NIR emission band peaked at 830 nm with a bandwidth of 135 nm under excitation at 450 nm. Through comprehensive structural and spectral analysis, this NIR band is attributed to the emission originating from Mn2+ ions within the MnO6 octahedra. Importantly, the formation of Mn2+–Mn2+ dimers breaks the spin‐forbidden rule and significantly enhances the transition probability, as supported by the excited state dynamic analysis. Consequently, the optimal ZAO: 0.70Mn2+ sample shows high internal/external photoluminescence quantum yields of 85.8%/36.9%, along with good thermal stability demonstrated by the emission intensity at 423 K retains 60% of that at 298 K. Finally, a prototype NIR pc‐LED device is fabricated by combining ZAO: 0.70Mn2+ phosphor with a 450 nm blue diode chip, generating an NIR output power of 28.84 mW at 100 mA. This study provides novel insights into high‐performance Mn2+‐activated NIR phosphors. [ABSTRACT FROM AUTHOR]

n‐C4H10 and iso‐C4H10 are both important petrochemical raw materials. Considering the coexistence of the isomers in the production process, it is necessary to achieve their efficient separation through an economical way. However, to obtain high‐purity n‐C4H10 and iso‐C4H10 in one‐step separation process, developing iso‐C4H10‐exclusion adsorbents with high n‐C4H10 adsorption capacity is crucial. Herein, we report a cage‐like MOF (SIFSIX‐Cu‐TPA) with small windows and large cavities which can selectively allow smaller n‐C4H10 enter the pore and accommodate a large amount of n‐C4H10 simultaneously. Adsorption isotherms reveal that SIFSIX‐Cu‐TPA not only completely excludes iso‐C4H10 in a wide temperature range, but also exhibits a very high n‐C4H10 adsorption capacity of 94.2 cm3 g−1 at 100 kPa and 298 K, which is the highest value among iso‐C4H10‐exclusion‐type adsorbents. Breakthrough experiments show that SIFSIX‐Cu‐TPA has excellent n/iso‐C4H10 separation performance and can achieve a record‐high productivity of iso‐C4H10 (3.2 mol kg−1) with high purity (>99.95 %) as well as 3.0 mol kg−1 of n‐C4H10 (>99 %) in one separation circle. More importantly, SIFSIX‐Cu‐TPA can realize the efficient separation of butanes at different flow rates, temperatures, as well as under high humid condition, which indicates that SIFSIX‐Cu‐TPA can be deemed as an ideal platform for industrial butane isomers separation. [ABSTRACT FROM AUTHOR]

All‐inorganic α‐phase CsPbI3 perovskite with a suitable bandgap and superb optoelectronic properties is transforming the landscape of perovskite photovoltaics, but its long‐term lability associated with "soft" ionic lattice still imposes a great challenge for practical applications. Herein, a unique solid‐solution fluorination strategy is proposed to deliver an "ideal" perovskite matrix of α‐phase CsPbI3 abundant with F ions through interlocking the soft lattice of CsPbI3 with cubic‐phase CsF·3/2HF. Such a sublattice interlocking can not only stabilize the soft lattice of α‐phase CsPbI3 perovskite nanocrystals but also passivate their notorious surface defects, thereby producing a "rigid" solid‐solution‐type perovskite/fluoride CsPbI3/CsF (termed as CsPbI3:F) nanocomposite with excellent long‐term stability and a near‐unity photoluminescence efficiency. Of particular note is that these CsPbI3:F nanocomposites can work well as effective grain boundary anchors to significantly improve the photovoltaic performance of perovskite solar cells because of their F‐rich perovskite lattice, achieving a T80 stability of 1500 h under continuous maximum power point tracking and AM 1.5G illumination without the need for encapsulation. This work paves a new way to deliver perovskite materials with desirable properties for photovoltaics. [ABSTRACT FROM AUTHOR]

The strategy of heavily doping Mn2+ not only enhances light-absorption intensity, but also sometimes induces the production of unique long-wavelength luminescence. However, the understanding of the luminescence mechanism remains limited. Herein, we investigated the Mn2+ concentration-dependent luminescence behavior of LaMgAl11O19: xMn2+ (LMAO : xMn2+) phosphors. Upon an excitation of 450 nm, the PL spectra of LMAO : xMn2+ transitioned from single green emission to dual-wavelength green/far-red emission, ultimately evolving into pure far-red emission by gradually increasing Mn2+ concentration. The green emission was attributed to tetrahedrally coordinated Mn2+, whereas the far-red emission originated from octahedral Mn2+ owing to its significantly prolonged lifetime. Notably, an energy transfer occurred between neighboring tetrahedral and octahedral Mn2+, resulting in their similar excitation spectra. Additionally, when the concentration of Mn2+ was further increased, the far-red emission spectrum underwent a sustained redshift, and broadband NIR luminescence peaking at 830 nm with a shortened lifetime emerged, suggesting its luminescence originates from Mn2+–Mn2+ dimers. Finally, leveraging the similar excitation spectra and distinct thermal quenching behaviors of the green and far-red emissions, we developed a novel FIR thermometer LMAO : 0.54Mn2+ demonstrating excellent temperature-sensing capability and repeatability. This study provides new insights into the heavily Mn2+-doped materials and advanced optical applications. [ABSTRACT FROM AUTHOR]

The one‐step efficient separation of high‐purity C2H4 from C2H4/C2H6 mixtures by hydrogen‐bonded organic frameworks (HOFs) faces two problems: lack of strategies for constructing stable pores in HOFs and how to obtain high C2H6 selectivity. Herein, we have developed a microporous Mortise‐Tenon‐type HOF (MTHOF‐1, MT is short for Mortise‐Tenon structure) with a new self‐assembly mode for C2H4/C2H6 separation. Unlike previous HOFs which usually possess discrete head‐to‐head hydrogen bonds, MTHOF‐1 is assembled by unique consecutive side‐by‐side hydrogen bonds, which result in mortise‐and‐tenon pores decorated with orderly arranged amide groups and benzene rings. As expected, MTHOF‐1 exhibits excellent stability under various conditions and shows clear separation trends for C2H6/C2H4. The IAST selectivity is as high as 2.15 at 298 K. More importantly, dynamic breakthrough experiments have demonstrated that MTHOF‐1 can effectively separate the C2H6/C2H4 feed gas to obtain polymer‐grade C2H4 in one step even under high‐humidity conditions. [ABSTRACT FROM AUTHOR]

Inherent "soft" ionic lattice nature of halide perovskite quantum dots (QDs), triggered by the weak Pb−X (X=Cl, Br, I) bond, is recognized as the primary culprit for their serious instability. A promising way is to construct exceedingly strong ionic interaction inside the QDs and increase their crystal cohesive energy by substituting the interior X− with highly electronegative F−, however, which is challenging and hitherto remains unreported. Here, a "whole‐body" fluorination strategy is proposed for strengthening the interior bonding architecture of QDs, wherein the F− are uniformly distributed throughout the whole nanocrystal encompassing both the interior lattice and surface, successfully stabilizing their "soft" crystal lattice and passivating surface defects. This approach effectively mitigates their intrinsic instability issues including light‐induced phase segregation. As a result, light‐emitting devices based on these QDs exhibit exceptional efficiency and remarkable stability. [ABSTRACT FROM AUTHOR]

H2O2 is a widely used eco‐friendly oxidant and a potential energy carrier. Photocatalytic H2O2 production from water and O2 is an ideal approach with the potential to address the current energy crisis and environmental issues. Three zig‐zag two‐dimensional coordination polymers (2D CPs), named CuX‐dptz, were synthesized by a rapid and facile method at room temperature, showing preeminent H2O2 photoproduction performance under pure water and open air without any additives. CuBr‐dptz exhibits a H2O2 production rate high up to 1874 μmol g−1 h−1, exceeding most reported photocatalysts under this condition, even comparable to those supported by sacrificial agents and O2. The coordination environment of Cu can be modulated by halogen atoms (X=Cl, Br, I), which in turn affects the electron transfer process and finally determines the reaction activity. This is the first time that 2D CPs have been used for photocatalytic H2O2 production in such challenging conditions, which provides a new pathway for the development of portable in situ H2O2 photosynthesis devices. [ABSTRACT FROM AUTHOR]