Search

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]