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The anhydrous proton conductivity of Im@IEF-11 resulting from the integration of imidazole and porous IEF-11 has been investigated, and the highest proton conductive value can reach up to 7.64 × 10−2 S cm−1. Furthermore, IEF-11 is also developed to reduce CO2 due to its reasonable structure and suitable energy band, and its CO formation rate is 31.86 μmol g−1 h−1. [ABSTRACT FROM AUTHOR]

The photocatalytic conversion of CO2 into widely adjustable syngas (CO/H2 mixture) has been considered as an extraordinarily promising but challenging strategy to realize high value-added utilization of CO2 to alleviate worldwide environmental problems and energy crisis. To achieve this goal, we report a newly designed crystalline covalent organic framework (COF-TVBT-Bpy) that embedded a series of metal active sites to efficiently convert CO2 and H2O into syngas under visible-light illumination. COF-TVBT-Bpy not only provides a coordination environment for the metal center, but also enhances electron delocalization by the extended conjugated moiety, thus facilitating electron transfer. The optimized Co@COF-TVBT-Bpy achieves the highest photocatalytic CO2-to-syngas conversion efficiency in pure CO2 (up to 2291.1 μmol g−1 h−1, CO/H2 ≈ 1 : 1). The intrinsic reason for a CO/H2 ratio of 1 : 1, electron transfer pathway, and syngas generation mechanism over Co@COF-TVBT-Bpy are explored by the combination of in situ measurements and theoretical calculations. The experimental results confirm that the ratio of CO/H2 can be widely modulated by adjusting the metal active sites and photoreaction conditions. This work proves the immense potential of utilizing COFs as platforms to anchor metal active sites for syngas formation and provides a facile method to regulate the ratio of syngas in a wide range. [ABSTRACT FROM AUTHOR]

Metal–organic frameworks (MOFs) provide an ideal platform for loading various guests owing to their available space, and can be developed as a class of multifunctional materials. Herein, we cover the design and synthesis of two kinds of exchanged frameworks with multifunctional applications based on H3ImDC and In(NO3)3·2H2O through guest exchange inside the framework. The guest ammonium ion (NH4+) and [Ru(2,2′-bipyridine)3]2+ (Rubpy) are selected to exchange the dimethylammonium cation (Me2NH2+) encapsulated within In-MOF, giving birth to two kinds of new MOFs, named NH4+@In-MOF and Rubpy@In-MOF respectively. The proton conduction of NH4+@In-MOF and the CO2 photoreduction of Rubpy@In-MOF are investigated. Under different test conditions, the proton conductive behaviors of NH4+@In-MOF are evaluated and the best proton conductive value can reach up to 9.81 × 10−3 S cm−1. Compared to the original In-MOF, Rubpy@In-MOF exhibits a significantly enhanced CO2 photoreduction performance under a pure CO2 atmosphere. Furthermore, its photocatalytic activity is retained even under a 10% CO2 gas atmosphere, displaying a synergistic effect between Rubpy and In-MOF24 within Rubpy@In-MOF. [ABSTRACT FROM AUTHOR]

Two unprecedented 3D porous anionic metal–organic frameworks, [Me2NH2]2[Cd2(bpdc)3]·4dma 1and [Me2NH2]2[Cd2(NH2bdc)3]·4dma 2(dma = N,N′-dimethylacetamide, bpdc = 4,4′-biphenyldicarboxylate, NH2bdc = 2-amino-1,4-benzenedicarboxylate) have been solvothermally synthesized with a dimethylammonium cations template. Both 1and 2are constructed from low-symmetry SBUs. 1has a chiral framework with helical nanotube-like channels, and 2has a MOF-5-like motif. The fluorescence, N2adsorption and ion-exchange properties for 1have been examined. [ABSTRACT FROM AUTHOR]

The anhydrous proton conductivity of Im@IEF-11 resulting from the integration of imidazole and porous IEF-11 has been investigated, and the highest proton conductive value can reach up to 7.64 × 10 -2 S cm -1 . Furthermore, IEF-11 is also developed to reduce CO 2 due to its reasonable structure and suitable energy band, and its CO formation rate is 31.86 μmol g -1 h -1 .

Metal-organic frameworks (MOFs) provide an ideal platform for loading various guests owing to their available space, and can be developed as a class of multifunctional materials. Herein, we cover the design and synthesis of two kinds of exchanged frameworks with multifunctional applications based on H 3 ImDC and In(NO 3 ) 3 ·2H 2 O through guest exchange inside the framework. The guest ammonium ion (NH 4 + ) and [Ru(2,2'-bipyridine) 3 ] 2+ (Rubpy) are selected to exchange the dimethylammonium cation (Me 2 NH 2 + ) encapsulated within In-MOF , giving birth to two kinds of new MOFs, named NH 4 + @In-MOF and Rubpy@In-MOF respectively. The proton conduction of NH 4 + @In-MOF and the CO 2 photoreduction of Rubpy@In-MOF are investigated. Under different test conditions, the proton conductive behaviors of NH 4 + @In-MOF are evaluated and the best proton conductive value can reach up to 9.81 × 10 -3 S cm -1 . Compared to the original In-MOF , Rubpy@In-MOF exhibits a significantly enhanced CO 2 photoreduction performance under a pure CO 2 atmosphere. Furthermore, its photocatalytic activity is retained even under a 10% CO 2 gas atmosphere, displaying a synergistic effect between Rubpy and In-MOF24 within Rubpy@In-MOF .

Two unprecedented 3D porous anionic metal-organic frameworks, [Me2NH2]2[Cd2(bpdc)3].4dma 1 and [Me2NH2]2[Cd2(NH2bdc)3].4dma 2 (dma = N,N'-dimethylacetamide, bpdc = 4,4'-biphenyldicarboxylate, NH(2)bdc = 2-amino-1,4-benzenedicarboxylate) have been solvothermally synthesized with a dimethylammonium cations template. Both 1 and 2 are constructed from low-symmetry SBUs. 1 has a chiral framework with helical nanotube-like channels, and 2 has a MOF-5-like motif. The fluorescence, N2 adsorption and ion-exchange properties for 1 have been examined.

A series of mixed-ligand coordination complexes, namely [Zn(L(1))(oba)] (), [Cd(L(1))(oba)] (), [Zn(2)(L(2))(oba)(2)].8H(2)O (), [Cd(2)(L(2))(oba)(2)].2H(2)O (), [Zn(3)(L(3))(oba)(3)] (), [Cd(2)(L(3))(oba)(2)].(L(3)) (), [Cd(L(4))(oba)].H(2)O () and [Cd(L(5))(oba)].3H(2)O (), where L(1) = 2-(2-pyridyl)imidazole, L(2) = 1,4-bis[2-(2-pyridyl)imidazol-1-yl]butane, L(3) = 1,4-bis[2-(2-pyridyl)imidazol-1-ylmethyl]benzene, L(4) = 1,3-bis[2-(2-pyridyl)imidazol-1-ylmethyl]benzene, L(5) = 1,2-bis[2-(2-pyridyl)imidazol-1-ylmethyl]benzene and H(2)oba = 4,4'-oxydibenzoic acid, have been synthesized under hydrothermal conditions. Their structures have been determined by single crystal X-ray diffraction analyses and further characterized by elemental analyses, IR spectra, and thermogravimetric (TG) analyses. In compounds and , oba(2-), L(1) ligand and Zn(II) or Cd(II) ions assemble to form the parallel chains or parallel sheets which are linked by the weak hydrogen bonding and pipi stacking interactions to give the 2D supramolecular sheet or 3D supramolecular net, respectively. For , L(2) ligands connect [Zn(oba)] chains to generate a unusual (10,3)-b topological structure which is the first example for eight-fold interpenetrating framework based on the (10,3)-b net. In , L(2) ligands link [Cd(oba)] double-chains to give a 2D sheet which is assembled by pipi stacking interactions to obtain a 3D supramolecular net. In , L(3) ligands link Zn(II) ions from alpha-Po net formed by Zn(II) ions and oba(2-) anions to show a novel 3D 8-connected self-penetrating framework with the unreported (4(16).6(11).8) topological structure. In , the double-chains constructed by Cd(II) and oba(2-) anions are linked by one kind of L(3) ligand to form a layer-like structure which is assembled by pipi stacking interactions to show a 3D supramolecular structure. In , oba(2-) anions coordinate to Cd(II) cations to form chains which are connected by L(4) to form a four-fold interpenetrating diamond network. In , the weak hydrogen bonding and pipi stacking interactions connect the [Cd(L(5))(oba)] chains to give a 2D supramolecular sheet. By careful inspections of the structures of , we believe that the different flexible and angular neutral ligands, coordination geometries of metal centers and weak interactions (hydrogen bonds and pipi stacking interactions) are crucial factors for the formation of the different structures. The photoluminescent properties of have been studied in the solid state at room temperature.

Inorganic-organic hybrid materials based on Keggin polyoxometalate building blocks combined with Cu(II)/Cu(I) and flexible fluconazole ligand [1-(2,4-difluorophenyl)-1,1-bis[(1H-1,2,4-triazol-1-yl)methyl]methanol] (Hfcz) have been obtained by hydrothermal methods, namely, [Cu(II)(2)(Hfcz)(4)(SiW(12)O(40))].3H(2)O (1), [Cu(II)(4)(fcz)(4)(H(2)O)(4)(SiMo(12)O(40))].6H(2)O (2), [Cu(II)(2)(fcz)(2)][Cu(II)(4)(fcz)(4)(SiW(12)O(40))][Cu(II)(2)(fcz)(2)(H(2)O)(2)(SiW(12)O(40))].6H(2)O (3), (Et(3)NH)(2)[Cu(I)(2)(Hfcz)(2)(SiW(12)O(40))].2H(2)O (4), (Et(3)NH)(2)[Cu(I)(2)(Hfcz)(2)(SiW(12)O(40))].H(2)O (5) and [Cu(I)(4)(Hfcz)(4)(SiMo(12)O(40))] (6). Their structures have been determined by single-crystal X-ray diffraction analyses, and the compounds are further characterized by elemental analyses, IR spectra and thermogravimetric (TG) analyses. In 1, Cu(II) cations are bridged by fluconazole ligands to form a 3D lvt coordination polymeric network, which is connected by (SiW(12)O(40))(4-) anions to form a complicated 3D (4,6)-connected framework with the topology of (4(2).6(4))(4(6).6(7).8(2))(2). In 2, two fcz(-) anions chelate two Cu(2+) cations to form a [Cu(fcz)](2)(2+) dimer, which is bridged by (SiW(12)O(40))(4-) polyanions to generate a 2D (4,4) grid. Compound 3 is formed by three types of co-crystallizing subunits including a dimer [Cu(fcz)](2)(2+), a dumbbell molecule [Cu(4)(fcz)(4)(SiW(12)O(40))] and an infinite chain {[Cu(2)(fcz)(2)(H(2)O)(2)(SiW(12)O(40))](2-)}(infinity). In compounds 4 and 5, Hfcz ligands link Cu(+) cations to generate 1D coordination polymeric units, and (SiW(12)O(40))(4-) polyanions connect these metal-organic units to form two types of (6(3)) sheets which are topological isomerism. In compound 6, (SiMo(12)O(40))(4-) polyanions fixed in Cu(I)-Hfcz square rings are further extended into a 2D sheet via linking Cu(I) atoms of different rings. By carefully inspection of the structures of 1-6, it is believed that various transition-metal organic units and Keggin polyanions with different coordination modes are important for the formation of the different structures. In addition, electrochemical behaviors of compounds 1, 2, 5 and 6 have been investigated.