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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]

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]

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]

Ultra‐broadband near‐infrared (NIR) phosphor‐converted light‐emitting diodes (pc‐LEDs) have great application prospects in research and industrial fields. However, simultaneously achieving highly efficient and ultra‐broad NIR emission in phosphor material remains a challenge. Herein, an ultra‐broadband NIR emission in the range of 800–1200 nm with ultra‐high emission efficiency of up to 64.2% is first achieved by substituting the Sc3+ site in Cs2NaScCl6 perovskite single‐crystal with a Cr3+ ion. By combining the experimental results with first‐principles calculations, an efficient charge transfer sensitization process from host to Cr3+ is found to be the fundamental reason for the ultra‐high NIR emission efficiency. Benefiting from the excellent efficiency and superior chemical resistance to heat and UV radiation, an ultra‐broadband NIR pc‐LED made of this phosphor demonstrates great potential in biomedical imaging, nondestructive testing, and night‐vision devices. [ABSTRACT FROM AUTHOR]

For high‐power white light‐emitting diode devices (WLEDs), phosphor ceramics were widely used because of their high thermal conductivity and temperature resistance. In this study, Y2.998Al5O12: 0.002Ce3+ ceramics were prepared via vacuum reaction sintering and treated by silicon carbide (SiC) abrasives with particle sizes of 8.6, 20, 25, 34, and 50 μm to obtain a single textured surface. The transmittance, reflectance, luminous efficiency (LE) and photoluminescence (PL) intensity of the ceramics were investigated with various surface roughness and different placement. Compared with the double polished (DP) samples, the PL intensity and LE of the single‐surface textured ceramics were greatly improved. It was shown that the roughest ceramics placed with the single polished (SP) side facing the direction of the excitation light (the SP‐forward YAG: Ce ceramics) showed the best performance. [ABSTRACT FROM AUTHOR]

The one-step efficient separation of high-purity C 2 H 4 from C 2 H 4 /C 2 H 6 mixtures by hydrogen-bonded organic frameworks (HOFs) faces two problems: lack of strategies for constructing stable pores in HOFs and how to obtain high C 2 H 6 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 C 2 H 4 /C 2 H 6 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 C 2 H 6 /C 2 H 4 . 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 C 2 H 6 /C 2 H 4 feed gas to obtain polymer-grade C 2 H 4 in one step even under high-humidity conditions., (© 2024 Wiley‐VCH GmbH.)

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., (© 2024 Wiley-VCH GmbH.)

H 2 O 2 is a widely used eco-friendly oxidant and a potential energy carrier. Photocatalytic H 2 O 2 production from water and O 2 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 H 2 O 2 photoproduction performance under pure water and open air without any additives. CuBr-dptz exhibits a H 2 O 2 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 O 2 . 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 H 2 O 2 production in such challenging conditions, which provides a new pathway for the development of portable in situ H 2 O 2 photosynthesis devices., (© 2023 Wiley-VCH GmbH.)