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Adsorption‐based removal of carbon dioxide (CO2) from gas mixtures has demonstrated great potential for solving energy security and environmental sustainability challenges. However, due to similar physicochemical properties between CO2 and other gases as well as the co‐adsorption behavior, the selectivity of CO2 is severely limited in currently reported CO2‐selective sorbents. To address the challenge, we create a bioinspired design strategy and report a robust, microporous metal–organic framework (MOF) with unprecedented [Mn86] nanocages. Attributed to the existence of unique enzyme‐like confined pockets, strong coordination interactions and dipole‐dipole interactions are generated for CO2 molecules, resulting in only CO2 molecules fitting in the pocket while other gas molecules are prohibited. Thus, this MOF can selectively remove CO2 from various gas mixtures and show record‐high selectivities of CO2/CH4 and CO2/N2 mixtures. Highly efficient CO2/C2H2, CO2/CH4, and CO2/N2 separations are achieved, as verified by experimental breakthrough tests. This work paves a new avenue for the fabrication of adsorbents with high CO2 selectivity and provides important guidance for designing highly effective adsorbents for gas separation. [ABSTRACT FROM AUTHOR]

A novel cluster-based MOF with uncommon multicentered ZnI–ZnI bonds {[K1.2Na2.8ZnI8(HL)12]·4H2O}n (HL = tetrazole monoanion) (1) was synthesized, which showed higher stability than the reported ZnI–ZnI bonded compounds. Moreover, 1 can effectively and circularly catalyze the cyclization of CO2 and aziridines or epoxides with five substituent groups. Importantly, this is the first time that the catalytic properties of MOFs with multicentered metal–metal bonded clusters as the catalyst have been studied. [ABSTRACT FROM AUTHOR]

The reaction of propargylic amines and CO2 can provide high‐value‐added chemical products. However, most of catalysts in such reactions employ noble metals to obtain high yield, and it is important to seek eco‐friendly noble‐metal‐free MOFs catalysts. Here, a giant and lantern‐like [Zn116] nanocage in zinc‐tetrazole 3D framework [Zn22(Trz)8(OH)12(H2O)9⋅8 H2O]n Trz=(C4N12O)4− (1) was obtained and structurally characterized. It consists of six [Zn14O21] clusters and eight [Zn4O4] clusters. To our knowledge, this is the highest‐nuclearity nanocages constructed by Zn‐clusters as building blocks to date. Importantly, catalytic investigations reveal that 1 can efficiently catalyze the cycloaddition of propargylic amines with CO2, exclusively affording various 2‐oxazolidinones under mild conditions. It is the first eco‐friendly noble‐metal‐free MOFs catalyst for the cyclization of propargylic amines with CO2. DFT calculations uncover that ZnII ions can efficiently activate both C≡C bonds of propargylic amines and CO2 by coordination interaction. NMR and FTIR spectroscopy further prove that Zn‐clusters play an important role in activating C≡C bonds of propargylic amines. Furthermore, the electronic properties of related reactants, intermediates and products can help to understand the basic reaction mechanism and crucial role of catalyst 1. [ABSTRACT FROM AUTHOR]

Based on the mixed ligands XN (4′-(4-pyridine)4,2′:2′,4″-terpyridine) and isophthalic acid (IPA), three new metal-organic frameworks (MOFs) {[M2(XN)2(IPA)2]•2H2O}n (M=Co (1), Mn (2), Ni (3)) were assembled and structurally characterized, presenting 3D pillar-chain feature structures. Stability measurements demonstrate that these compounds possess high thermostability and can endure different organic solvents as well as various acid/base solutions with pH range of 1 to 14. Importantly, compounds 1–3 can serve as high-efficiency catalysts for the transformation of CO2 and aziridines to form high-value oxazolidinones under mild conditions, exhibiting excellent cyclicity at least five times. [ABSTRACT FROM AUTHOR]

Assembled from [Th48Ni6] nanocages, the first transition‐metal (TM)‐thorium metal–organic framework (MOF, 1) has been synthesized and structurally characterized. 1 exhibits high solvent and acid/base stability, and resistance to 400 kGy β irradiation. Notably, 1 captures ReO4− (an analogue of radioactive 99TcO4−, a key species in nuclear wastes) with a maximum capacity of 807 mg g−1, falling among the largest values known to date. Furthermore, 1 can enrich methylene blue (MB) and can also serve as an effective and recyclable catalyst for CO2 fixation with epoxides; there is no significant loss of catalytic activity after 10 cycles. Theoretical studies with nucleus‐independent chemical shifts and natural bond orbital analysis reveal that the [Th6O8] clusters in 1 have a unique stable electronic structure with (d–p)π aromaticity, partially rationalising 1′s stability. Resistance is useful: The stable [Th48Ni6] nanocage‐based metal–organic framework (MOF) is radiation resistant, effectively and selectively captures ReO4− and catalytically converts CO2 into epoxides. The aromatic character of the Th6O8 clusters accounts for the stability of the MOF. [ABSTRACT FROM AUTHOR]

A novel two-fold interpenetrated 3D metal–organic framework {[Zn(DCTP)]·4.2H2O}n (1) (H2DCTP = 4′-(3,5-dicarboxyphenyl)-4,2′:6′,4′′-terpyridine) was synthesized from a pyridine–carboxylic ligand and Zn(OAc)2 under solvothermal conditions. Along the a-axis, a large pore exists in 1 with a size of 12.5 × 14.7 Å, and after removing solvent molecules, the porosity is 22.4%. Thermogravimetric analysis (TGA) and powder X-ray diffraction (PXRD) show that 1 has high thermal, pH, and solvent stability. Importantly, 1 is able to significantly capture CO2 at up to 67 cm3 g−1 at 273 K. Furthermore, 1 can effectively catalyze the cycloaddition reaction of CO2 with epoxides, and it can be recycled at least five times without a change in catalytic efficiency. Additionally, 1 can serve as a sensitive and recyclable luminescent probe to detect CrO42−/Cr2O72−, and the detection limit can reach 1 × 10−6 M and 1.5 × 10−6 M, respectively. [ABSTRACT FROM AUTHOR]

A multifunctional metal–organic framework (1) containing 24-nuclear zinc nanocages shows high solvent- and pH-stability. Compound 1 can be employed as a catalyst for the conversion of CO2 with aziridines or epoxides, which can be reused at least ten times just by a simple and rapid method. The PXRD of compound 1 after ten recyclings remains well consistent with the original one. The inductively coupled plasma measurement of a reaction filtrate revealed that only trace amount leakage of Zn2+ was observed, indicating that the framework did not collapse after recyclings. Compound 1 can effectively catalyze the cycloaddition reaction of CO2 and five aziridines or five epoxides with different substituent groups. To our knowledge, this is the first multifunctional MOF-based catalyst used for the conversion of CO2 with aziridines or epoxides. Furthermore, luminescence investigations reveal that compound 1 can also act as a luminescent probe for chromium(vi) anion species, which is seriously harmful to humans and the environment. After five cycle tests, the PXRD of compound 1 is still in accordance with the original one, indicating that compound 1 can serve as a circulatory luminescent probe for Cr(vi) anions. [ABSTRACT FROM AUTHOR]

A novel triangular [Mn3] cluster-based 3D ferrimagnet [Na2Mn3(SO4)3(μ3-OH)2(μ2-OH2)2]n (1) was structurally and magnetically characterized. It exhibited both long-range magnetic ordering (TC = 12.0 K) and spin glass behaviour around 10 K and a butterfly-shaped magnetic hysteresis loop was observed. A peak (14.4 J kg−1 K−1) in the −ΔSmvs. temperature curve was obtained at 13.5 K. It is rather rare that the magnetocaloric effect of a ferrimagnet was explored and that the peak in the −ΔSmvs. temperature curve occurs above 10 K. [ABSTRACT FROM AUTHOR]

A novel two-fold interpenetrated 3D metal–organic framework {[Zn(DCTP)]·4.2H2O}n (1) (H2DCTP = 4′-(3,5-dicarboxyphenyl)-4,2′:6′,4′′-terpyridine) was synthesized from a pyridine–carboxylic ligand and Zn(OAc)2 under solvothermal conditions. Along the a-axis, a large pore exists in 1 with a size of 12.5 × 14.7 Å, and after removing solvent molecules, the porosity is 22.4%. Thermogravimetric analysis (TGA) and powder X-ray diffraction (PXRD) show that 1 has high thermal, pH, and solvent stability. Importantly, 1 is able to significantly capture CO2 at up to 67 cm3 g−1 at 273 K. Furthermore, 1 can effectively catalyze the cycloaddition reaction of CO2 with epoxides, and it can be recycled at least five times without a change in catalytic efficiency. Additionally, 1 can serve as a sensitive and recyclable luminescent probe to detect CrO42−/Cr2O72−, and the detection limit can reach 1 × 10−6 M and 1.5 × 10−6 M, respectively. [ABSTRACT FROM AUTHOR]

Tunable structures and magnetocaloric effect (MCE) of seven MOFs with [Gd n ] as nodes are explored. The [Gd n ] node is realized from mononuclear [Gd] to binuclear paddle-wheel [Gd 2 ], tetranuclear tetrahedral [Gd 4 ], and pentanuclear trigonal bipyramidal [Gd 5 ]. Meanwhile, the magnetic entropy changes from 19.4 to 46.0 J·kg -1 ·K -1 . The results reveal that the effect of magnetic density on MCE plays a dominant role for Gd 3+ -based compounds, and high spin ground state of Mn 2+ (S = 5/2) is more favorable to achieve high MCE than that with Zn 2+ , Co 2+ , and Ni 2+ (Co 2+ , S = 3/2; Ni 2+ , S = 1). To our knowledge, it is the first report that MCE is controlled by various clusters as nodes in MOFs.