A mixed-ligand-based thermo-chemically robust and undulated metal-organic framework (MOF) is developed that embraces carboxamide moiety-grafted porous channels and activation-induced generation of open-metal site (OMS). The guest-free MOF acts as an outstanding heterogeneous catalyst in Hantzsch condensation for electronically assorted substrates with low catalyst loading and short duration under greener conditions than the reported materials. Besides Lewis acidic OMS, the carboxamide group activates the substrate via two-point hydrogen bonding, highlighting the effectiveness of custom-made functionalities in this multi-component reaction.
View Article and Find Full Text PDFMetal-organic frameworks (MOFs) are versatile nanoporous materials for a wide variety of important applications. Recently, a handful of MOFs have been explored for the storage of toxic fluorinated gases (Keasler et al. 1455), yet the potential of a great number of MOFs for such an environmentally sustainable application has not been thoroughly investigated.
View Article and Find Full Text PDFMetal-organic frameworks (MOFs) represent a distinctive class of nanoporous materials with considerable potential across a wide range of applications. Recently, a handful of MOFs has been explored for the storage of environmentally hazardous fluorinated gases (Keasler et al. 2023, 381, 1455), yet the potential of over 100,000 MOFs for this specific application has not been thoroughly investigated, particularly due to the absence of an established force field.
View Article and Find Full Text PDFStimuli-responsive emission color modulation in fluorescent metal-organic frameworks (MOFs) promises luminescence-ink-based security application, while task-specific functionality-engineered pores can aid fast-responsive, discriminative, and ultralow detection of harmful organo-aromatics in the aqueous phase. Considering practical applicability, a self-calibrated fluoro-switch between encrypted and decrypted states is best suited for antiforgery measures, whereas image-based monitoring of organo-toxins by repetitive and handy methods over multiple platforms endorses in-field sensory potential. Herein, we constructed a mixed-ligand based chemically stable and bilayered-pillar MOF from -NH-hooked pyridyl linker and tricarboxylate ligand that embraces negatively charged [Cd(μ-OH)(COO)] node and shows pore-space-partitioning by nitrogen-rich flanked organic struts.
View Article and Find Full Text PDFMore than the permissible limit of acidic gases like CO, SO, and NO in the atmosphere are responsible for the formation of acid rain, the greenhouse effect and many other undesirable environmental hazards. So, the capture and utilization of these gases are essential for mankind. Herein, we proposed an azo-based square pillared MOF, [Ni(MF)(1,2-bis(4-pyridy)diazene)], with the CUS metal site, M = Al/Fe, for the selective capture and conversion of acidic gas molecules into commodity chemicals such as cyclic carbonate, sulphite and nitrite.
View Article and Find Full Text PDFA multifaceted metal-organic framework (MOF) with task-specific site-engineered pores can promise high-temperature and moisture-tolerant capture and non-redox fixation of CO under mild conditions as well as ultrasensitive detection of carcinogenic contaminants in water. Herein, we report a pillar-bilayered MOF that holds a nanochannel with contrasting functionalities for both these sustainable applications with improved performance characteristics. The twofold entangled robust framework exhibits CO adsorption at elevated temperatures with considerable MOF-gas interaction.
View Article and Find Full Text PDFAcute detection of assorted classes of organo-toxins in a practical environment is an important sustainable agenda, whereas cooperative and recyclable catalysis can mitigate hazards by minimizing energy requirements and reducing waste generation. We constructed an acid-/base-stable Co(II)-framework with a unique network topology, wherein unidirectional porous channels are decorated by anionic [Co(μ-OH)(COO)(HO)] secondary building units and neutral [CoN(COO)] nodes. An intense luminescent signature of the hydrolytically robust framework is harnessed for the selective, fast-responsive, and regenerable detection of two detrimental organo-aromatics, 4-aminophenol (4-AP) and 2,4,6-trinitrophenol (TNP).
View Article and Find Full Text PDFThe anthropogenic emission of greenhouse gases, mainly CO, is considered to be one of the most challenging environmental threats related to global climatic change. Herein, for the first time, we accurately interpreted the interaction of guest molecules such as HO, CO and N, the main constituent of flue gas, to a coordinatively unsaturated (CUS) square pillared fluorinated metal organic framework (MOF) using a grand canonical Monte Carlo (GCMC) simulation with the help of a specific forcefield. This specific forcefield is derived from the interaction energy profile of the guest molecules to the framework attained from the periodic-density functional theory (DFT) calculations.
View Article and Find Full Text PDFA series of highly thermally and hydrolytically stable porous solids with intriguing properties of zirconium- and hafnium-based metal-organic frameworks (MOFs) [Dresden University of Technology (DUT) series] was synthesized. The DUT MOFs were found to be effective catalysts for both epoxide-CO cycloaddition reactions and the catalytic transfer hydrogenation (CTH) of ethyl levulinate (EL). In particular, 12-connected DUT-52(Zr) showed higher catalytic activity than eight- and six-connected catalysts in the synthesis of cyclic carbonates as well as in the production of γ-valerolactone (GVL).
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