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Due to the slow kinetic nature of the oxygen evolution reaction (OER), the development of electrocatalysts with high efficiency, stability, and economy for oxygen production using metal–organic framework (MOF) materials is still a challenging research topic. In this work, we chose the different concentrations of FeS adsorption to encapsulate metal cobalt-based ZIF-67 MOF for preparing a series of electrocatalysts (ZIF1FeSx, x= 0.2, 0.5, 0.75, and 1), which were mainly explored for the electrocatalytic OER. Among them, ZIF1FeS0.5has excellent electrocatalytic activity for OER, which can be driven by low overpotentials of 276 and 349 mV at 10 and 50 mA cm–2current densities, and more than 92% of the initial overpotential can be maintained after 100 h of continuous OER at 10 mA cm–2current density. This is mainly due to the electronic interactions between the cobalt-based MOF and the FeS, which shift the electronic state of the active metal center to a higher valence state for increasing the number of active sites and enhancing the efficiency of electron transfer to facilitate the OER course. This work may contribute to the design of effective catalysts for the OER during the electrolysis of alkaline solutions.

Separating acetylene (C2H2) from other light hydrocarbons and carbon dioxide (CO2) mixtures under mild conditions poses significant challenges due to the remarkably similar properties between C2H2and those gases. For the goal of C2H2separation, a F-functionalized organic linker, H2F-PyIP = 2-fluorine-5-(4-pyridyl)isophthalic acid, was designed, and the corresponding metal–organic framework (MOF), {[Co2(F-PyIP)2DMF]·4H2O}n(1), was constructed. The MOF with open channels decorated by the active sites of the F groups revealed the exceptional C2H2uptake and selectivity over CO2, C2H4, and CH4. The breakthrough experiments with different molar ratios of C2H2–C2H4, C2H2–CO2, and other gas mixtures further verified superior separation capacity of the MOF. In particular, the dynamic separation time intervals for gas mixtures (C2H2/CO2= 1:1, 1:5, 1:10, and 1:20) fell in the range 30–44 min, highlighting the potential of the MOF for tackling the challenging C2H2/CO2separation process.

Herein, we used the 4-fluoro-[1,1′-biphenyl]-3,4′,5-tricarboxylic acid (H3fbptc) ligand to design and construct a new metal–organic framework (MOF), [Cu3(fbptc)2(H2O)3]·3NMP (1), which possesses rich accessible metal sites and F functional groups in the porous walls and shows high uptake for C2H2(119.3 cm3g–1) and significant adsorption selectivity for C2H2over CH4(14.4) and CO2(3.6) at 298 K and 100 kPa. In particular, for the gas mixtures of C2H2–CH4and C2H2–CO2, the MOF reveals large breakthrough time ratios (C2H2/CH4= 13, C2H2/CO2= 5.9), which are particularly prominent in dynamic breakthrough experiments, also confirming the excellent potential for the practical separation of C2H2from two-component mixtures (C2H2–CH4and C2H2–CO2) and even three-component mixtures (C2H2–CO2–CH4).

Recently, the development of porous absorbents for efficient CO2and I2capture has attracted considerable attention because of severe global climate change and environmental issues with the nuclear energy. Hence, a unique porous metal–organic framework (MOF), {[Co(L)]·DMF·2H2O}n(1, DMF = N,N-dimethylformamide) with uncoordinated N atoms was rationally constructed via using a heterofunctional 4,6-bis(4′-carboxyphenyl)pyrimidine (H2L) linker. Interestingly, 1exhibits exceptional properties for I2sorption, CO2capture, and catalytic conversion. Particularly, I2can be efficiently removed in both vapor and solution forms, and the adsorption amount can reach 676.25 and 345.28 mg g–1, respectively. Furthermore, complex 1displays high adsorption capacity for CO2(53.78 cm3g–1, 273 K). Consequently, 1is expected to be a promising and practical material for environmental purification due to its excellent adsorption properties.

Energy saving and emission reduction have always been the goal of separation and catalysis pursued in industrial production. Metal–organic frameworks (MOFs) are leading porous crystal materials with unique advantages in these fields. Based on an amide-modified ligand 5-(ethyl oxamate)-isophthalic acid (H2EtL), a new porous indium-organic framework (Me2NH2)1.5[In1.5L2]·2DMF·2H2O (1) was synthesized and structurally characterized. The unique porous environment gives it dual functional advantages in separation and catalysis. At room temperature, 1possesses excellent adsorption capacities for C2hydrocarbons and CO2, showing good separation behaviors for C2hydrocarbons/CO2on CH4and C2H2on CO2, which is conducive to efficient purification of CH4and C2H2confirmed by the breakthrough experiment. Meanwhile, catalytic results indicate that 1can be used as a good catalyst for effective fixation of CO2under mild conditions to form cyclic carbonates.

A bifunctional ligand strategy for modification of the functional pores is of great significance in the structural design of metal–organic frameworks (MOFs). Herein, a new 2-fold interpenetrated “pillared-layer” 3D Co-MOF, {[Co(HL)(4,4′-bipy)]·DMF·2H2O}n(1), was successfully synthesized by using two kinds of ligands, imidazolecarboxylic acid and pyridine. The metal–carboxylic layers are pillared by the 4,4′-bipy ligand, displaying a 3D framework with rectangular 3D channels (high BET surface of 190.9 m2g–1and maximum aperture of 3.9 Å) that are decorated with abundant uncoordinated N and O atoms. 1shows good water stability and thermal stability (320 °C). The proper pores and active sites endowed 1with a selective adsorption of Congo red in aqueous solution. In addition, a high CO2adsorption capacity and an excellent CO2chemical conversion were observed.

Utilizing 5,5′-oxidiisophthalic acid (H4odip) ligand, one 3D framework {[Ni2(odip)(H2O)4(DMF)]·DMF·2H2O}n(1) with a rare 3-nodal (3,3,4)-connected topological net based on two types of Ni12(odip)12and Ni24(odip)12nanocages was prepared. To exploit the advantage of high porosity, 1was employed as an MOF matrix, and then photoactive Eu3+ions were introduced through a facile soaking method to get Eu3+functionalized MOF composite Eu3+@1. Luminescent sensing experiment demonstrated that Eu3+@1has the potential to serve as a sensitive, recyclable, and fast luminescent probe for aspartic acid, with a quenching constant of 1.565 × 103L/mol. The result offers a new possibility for many MOF materials which are nonemissive and/or difficult to synthesize directly to realize luminescent sensing function similar to lanthanide MOFs. Moreover, 1reveals a ferromagnetic character in the range of 6–35 K. The dynamic magnetization measurements displayed no frequency dependencies, suggesting the absence of slow magnetic relaxation.

Based on the mixed carboxylate ligands synthesis strategy, an indium–organic framework, (Me2NH2)1.5[In1.5(FBDC)(BDC)]·2.5NMF·CH3CN (1) has been constructed by using the mixed (2,5-di(2′,5′-dicarboxylphenyl)-difluorobenzene (H4FBDC) and terephthalic acid (H2BDC). Compound 1contains a 3D intersecting pore system which surface is modified by F atoms, and it has excellent stability in pH = 2−12 aqueous solutions. The activated 1shows high separation for C2H2/CO2and C2H2/CH4. Moreover, 1not only has strong luminescence but also has the high selectivity and sensibility of fluorescence detection to nitrofurazone (NZF) in antibiotic sensing experiments, which can be used as a luminescence sensor for NZF detection.