Nowadays, the practical applications of metal− organic framework (MOF)-based fluorescence detectors are severely hindered because of the complex synthesis process of linkers or heavy metal contamination. The development of a simple, inexpensive, and environmentally friendly fluorescence sensing system remains a huge challenge. In this study, we designed and synthesized a TPE@γ-CD-MOF-K complex using the facile in situ encapsulation method. The unique pore structure of γ-CD-MOF allowed it to effectively include TPE and explosives as guests simultaneously. The TPE@γ-CD-MOF-K showed stronger fluorescence emission than TPE and sensitive fluorescence quenching activities in response to nitro-aromatic compounds in the liquid phase with detection limits as low as 3 ppm. Furthermore, TPE@γ-CD-MOF-K can also effectively detect nitro-aromatic compounds in the solid state, which is very convenient for practical detection of explosives. The unique pore structure of γ-CD-MOF-K and the interaction between K + and nitro compounds play important roles in solid-state quenching.

Mixed matrix membranes (MMMs) for CO 2 separation have overcome the trade-off between gas permeability and gas selectivity to some extent. However, most MMMs still are prepared in lab-and pilot-scales since the permeability and selectivity of CO 2 are not good enough to reach the economically available requirements. Moreover, the fabrication of few MMMs with good separation performance is time-consuming or need harsh conditions. In this study, a novel MOF-based composite membrane (PANγ-CD-MOF-PU membrane) was successfully fabricated by a facile and fast spin-coating method. In the two-step coating process, we applied a uniform selective layer of γ-cyclodextrin-MOF (γ-CD-MOF) on porous polyacrylonitrile and then coated a layer of polyurethane on the γ-CD-MOF layer. The entire membrane formation process was about 30 s. The formation of a unique γ-CD-MOF layer greatly improved the separation ability of CO 2 (the CO 2 permeability is 70.97 barrers; the selectivity to CO 2 /N 2 and CO 2 /O 2 are 253.46 and 154.28, respectively). The gas separation performance can exceed the Robeson upper limit obviously and the selectivity is better than other MOF-based composite membranes. In addition, the PAN-γ-CD-MOF-PU membrane is strong and flexible. Therefore, the PAN-γ-CD-MOF-PU membrane developed in this study has great potential in large-scale industrial separation of CO 2 .

γ‐cyclodextrin (CD)‐metal‐organic framework (MOF)‐K is developed as a new kind of green template for the preparation of hierarchical porous carbon (HPC). Three‐level porous structure (micro‐, meso‐, and macro‐pores) has been successful constructed by calcined γ‐CD‐MOF‐K at 600°C. The fabricated carbon (HPC‐600) shows good microwave adsorption ability due to its unique hierarchical porous structure (macropores allow microwave enter the interior of the absorbents, and then micro‐ and meso‐pores attenuate the incident microwave effectively by multiple reflections and polarization loss caused.) The minimum reflection loss (RL) is − 23.5 dB and the effective absorption bandwidth (EAB, RL≤− 10 dB) is 4.3 GHz. This work provides a good reference for efficient and environment‐friendly microwave absorbents. In addition, the applications of HPC‐600 may further expand to adsorption, sensing and supercapacitors due to the hierarchically porous structure.

No abstract

High strength and ductility materials are demand for modern various applications. In order to surmount the inherent trade-off between toughness and stiffness for most elastomers, we developed a strategy which...