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Selective adsorption of paraffins over olefins (mostly C2 and C3) by porous solids could offer tremendous advantages for the purification of olefins, which is, however, challenging as it has stringent requirements on the pore dimensions and pore surface chemistry of the adsorbent. We report here a metal-organic framework (MOF) with novel topology, Y3(μ3-OH)(TCMPB)2 (denoted as HIAM-316, TCMPB4− = 1,2,4,5-tetra(4-carboxy-3-methylphenyl)benzene), which shows reversed separation of C2H6/C2H4 and C3H8/C3H6 simultaneously. The ideal adsorbed solution theory (IAST) selectivities for equimolar binary mixtures of C2H6/C2H4 and C3H8/C3H6 were calculated to be 1.67 and 1.23 at 1 bar and 298 K for HIAM-316. Its capability of removing paraffines from paraffin/olefin mixtures is validated by breakthrough measurements. Molecular simulations reveal that the preferential adsorption of paraffins over olefins by HIAM-316 may be attributed to the abundant carboxylate oxygen atoms along its channel. [ABSTRACT FROM AUTHOR]

Metal–organic frameworks (MOFs) have been widely studied as new materials, and many structural regulation strategies have been reported. We report a new defective-MOF design strategy that involves a continuous process of pore space partition, metal center exchange, and ligand removal. In the whole process, the single crystal of MOF is well maintained, which not only points out a rare and clear route for the structure transformation process but also provides an indirect synthesis method for defective materials, which cannot accurately control the vacancy position. It was interesting to find that the removal of the selected ligand endows the MOF with larger pores, higher stability and excellent performance in the selective adsorption and separation of C2H4/C3H6 mixtures and natural gas mixtures. [ABSTRACT FROM AUTHOR]

A honeycomb porous cadmium(II) metal–organic framework {[Cd(L)(H2O)] ⋅ NMP ⋅ 5H2O}n (1, H2L=1‐(4‐carboxyphenyl)‐1H‐pyrazole‐3‐carboxylic acid and NMP=1‐methyl‐2‐pyrrolidinone) was obtained using the solvothermal method. The luminescent molecules rhodamine B (RhB) and fluorescein (FL) were encapsulated in 1 using the immersion method to prepare RhB@1 and FL@1 dual emission composites. Additionally, a series of RhBx/FL1‐x@1 composites with varying luminescence properties were generated by altering the molar ratio of RhB to FL. Furthermore, the photoluminescence of RhB@1 and FL@1 was demonstrated to be caused by photoelectron transfer and fluorescence resonance energy transfer from 1 to the encapsulated guest module. Notably, RhB@1 showed the considerable improvement in fluorescence selectivity and detection limit (10−6 M) for metronidazole and dimetronidazole with remarkable recyclability. [ABSTRACT FROM AUTHOR]

2-(2-Methoxyethoxy)ethanol (MEEA) can cause DNA damage and teratogenesis, and the biomarker of MEEA is 2-(2-methoxyethoxy)acetic acid (MEAA). Therefore, portable and accurate monitoring of MEAA has far-reaching significance to ensure human health. In this work, a series of isometric three-dimensional (3D) lanthanide metal–organic frameworks (Ln-MOFs) {[Ln0.5(L)(H2O)]·1.5H2O}n (1-Ln, Ln = Eu, Tb, EuxTb1−x) were synthesized by using 1-(4-carboxyphenyl)-1H-pyrazole-4 carboxylic acid (H2L) and Ln3+. 1-Eu showed excellent sensing performance for MEAA with ultra-low detection limit (0.39 μM) and fast response time (within 1 min). To enhance the practicability of 1-Eu, three visual detection strategies of MEAA were provided. The polytetrafluoroethylene (PTFE) fluorescence film (Film@1-Eu) had a detection limit as low as the ppm level, and the fluorescence test paper achieved quantitative MEAA detection by combining with a smartphone sensing platform. In addition, a portable intelligent logic detector based on 1-Eu was designed by introducing a logic gate strategy for the real-time detection of MEAA. Notably, a Ln-MOF texture code with a high encryption algorithm and information density was designed for anti-counterfeiting labels on merchandise, utilizing the distinctive tuneable emission characteristic of 1-Ln. This study not only achieved the first visual detection of MEEA but also provided novel insights for the design of anti-counterfeiting materials. [ABSTRACT FROM AUTHOR]

The direct C−H to C−N bond conversion at room temperature using heterogeneous visible‐light catalysts is both interesting and challenging. Herein, we disclosed visible‐light‐promoted hydroacylation of azodicarboxylates using uranyl‐organic framework [UO2(OH)(cpt)]n (Ucpt, Hcpt=4‐(4′‐carboxyphenyl)‐1,2,4‐triazole) as an efficient heterogeneous hydrogen atom transfer photocatalyst. In this procedure, diverse benzaldehydes are compatible using dimethyl carbonate (DMC) as a green solvent at room temperature, achieving direct conversion of C−H to C−N bond with excellent yields (up to 99%). The key to excellent catalytic activity lies in the fact that the coordination of the conjugated ligand changes the HOMO energy level of Ucpt, resulting in more active sites and longer‐lived photo excitons. Simultaneously, this heterogeneous photocatalyst can be easily separated and reused for seven successive cycles and maintain high catalytic activity, showing outstanding sustainability and recyclability. [ABSTRACT FROM AUTHOR]