Interpenetrated Framework Research Articles

Ultrasound assisted synthesis of amide functionalized metal-organic framework for nitroaromatic sensing

Nano plates of zinc(II) based metal-organic framework (MOF) were prepared via ultrasonic method without any surfactants at room temperature and atmospheric pressure. Control of particle size and morphology was enhanced in this synthesis method. Nano plates of an interpenetrated amide-functionalized metal-organic framework, [Zn2(oba)2(bpfb)]·(DMF)5, TMU-23, (H2oba = 4,4′-oxybis(benzoic acid); bpfb = N,N′-bis-(4-pyridylformamide)-1,4-benzenediamine, DMF = N,N-dimethyl formamide), was synthesized under ultrasound irradiation in different concentrations of initial precursor. The nano structure and morphology of the synthesized MOF were characterized by Field Emission Scanning Electron Microscopy (FE-SEM), powder X-ray diffraction, thermo gravimetric analysis (TGA), elemental analysis and FTIR spectroscopy. Moreover, Fluorescence emissions of nanoplates have been studied. Amide-functionalized MOF shows high selectivity for sensing of nitroaromatic compounds such as nitrophenol, nitroaniline, and nitrobenzene in acetonitrile solution. Fluorescence intensity decreased with increasing contents of nitroaromatics in acetonitrile solution due to fluorescence quenching effect.

Highly Interpenetrated Robust Microporous Hydrogen-Bonded Organic Framework for Gas Separation

A hydrogen-bonded organic framework (HOF), HOF-11, has been successfully prepared by the slow diffusion of hexane into a tetrahydrofuran solution of tris(4-carboxyphenyl)amine (TCPA). HOF-11 has been characterized by single-crystal and powder X-ray diffraction analysis, which is composed of TCPA ligands connected by the intermolecular hydrogen-bonding interactions in the carboxylic group dimer, showing 11-fold interpenetrated three-dimensional hydrogen-bonded networks in a (10,3)-b topology with the pore size of 6.2 × 6.8 A2. The permanent porosity of degassed HOF was demonstrated by virtue of the CO2 sorption and selective gas adsorption.

Structural Consequences of 1,4-Cyclohexanedicarboxylate Cis/Trans Isomerism in Uranyl Ion Complexes: From Molecular Species to 2D and 3D Entangled Nets.

trans-1,4-Cyclohexanedicarboxylic acid (t-1,4-chdcH2) or the commercially available mixture of the cis and trans isomers (c,t-1,4-chdcH2) has been used in the synthesis of a series of 14 uranyl ion complexes, all obtained under solvohydrothermal conditions, some in the presence of additional metal cations and/or 2,2'-bipyridine (bipy). With its two isomeric forms having very different shapes and its great sensitivity to the experimental conditions, 1,4-chdc2- appears to be suitable for the synthesis of uranyl ion complexes displaying a wide range of architectures. Under the conditions used, the pure trans isomer gives only the complexes [UO2(t-1,4-chdc)(H2O)2] (1) and [UO2(t-1,4-chdc)] (2), which crystallize as one- and two-dimensional (1D and 2D) species, respectively. Complexes containing either the cis isomer alone or mixtures of the two isomers in varying proportion were obtained from the isomer mixture. The neutral complexes [UO2(c-1,4-chdc)(DMF)] (3) and [UO2(c-1,4-chdc)(bipy)] (4) are 2D and 1D assemblies, respectively, while all the other complexes are anionic and include various counterions. [C(NH2)3]3[H2NMe2][(UO2)4(c-1,4-chdc)6]·H2O (5) crystallizes as a three-dimensional (3D) framework with {103} topology. While [H2NMe2]2[(UO2)2(c-1,4-chdc)2(t-1,4-chdc)]·DMF·2H2O (6) is a 1D ladderlike polymer, [H2NMe2]2[(UO2)2(c-1,4-chdc)(t-1,4-chdc)2]·2H2O (7), which differs in the cis/trans ratio, is a 3-fold 2D interpenetrated network with {63} honeycomb topology. The related [H2NMe2]2[(UO2)2(c,t-1,4-chdc)3]·2.5H2O (8), with one disordered ligand of uncertain geometry, is a 3-fold 3D interpenetrated system. The two isomorphous complexes [Co(bipy)3][(UO2)2(c-1,4-chdc)3]·1.5H2O (9) and [Cd(bipy)3][(UO2)2(c-1,4-chdc)3]·1.5H2O (10) form 3D frameworks with the {103} srs topological type. In contrast, [Ni(bipy)3]2[(UO2)4(c-1,4-chdc)2(t-1,4-chdc)(NO3)6]·2H2O (11) is a molecular, tetranuclear complex due to the presence of terminal nitrate ligands. A 2-fold 3D interpenetration of frameworks with {103} ths topology is observed in [Cu(bipy)2]2[(UO2)2(c-1,4-chdc)2(t-1,4-chdc)]·2H2O (12), while [Zn(bipy)3][(UO2)2(c-1,4-chdc)3]·4H2O (13) crystallizes as a 2D net with the common {4.82} fes topological type. The additional PbII cation is an essential part of the 3D framework formed in [UO2Pb2(c-1,4-chdc)(t-1,4-chdc)2(bipy)2] (14), in which uranyl and its ligands alone form 1D subunits. Together with previous results, the solid-state uranyl emission properties of seven of the present complexes evidence a general trend, with the maxima for the complexes with O6 equatorial environments being blue-shifted with respect to those for complexes with O5 environments.

Modifying electron transfer between photoredox and organocatalytic units via framework interpenetration for \u03b2-carbonyl functionalization

Modifying electron transfer pathways is essential to controlling the regioselectivity of heterogeneous photochemical transformations relevant to saturated carbonyls, due to fixed catalytic sites. Here we show that the interpenetration of metal–organic frameworks that contain both photoredox and asymmetric catalytic units can adjust the separations and electron transfer process between them. The enforced close proximity between two active sites via framework interpenetration accelerates the electron transfer between the oxidized photosensitizer and enamine intermediate, enabling the generation of 5πe− β-enaminyl radicals before the intermediates couple with other active species, achieving β-functionalized carbonyl products. The enriched benzoate and iminium groups in the catalysts provide a suitable Lewis-acid/base environment to stabilize the active radicals, allowing the protocol described to advance the β-functionalization of saturated cyclic ketones with aryl ketones to deliver γ-hydroxyketone motifs. The homochiral environment of the pores within the recyclable frameworks provides additional spatial constraints to enhance the regioselectivity and enantioselectivity.

Mesoporous MnO/C-N Nanostructures Derived from a Metal-Organic Framework as High-Performance Anode for Lithium-Ion Battery.

By application of newly designed ligand 5-(3-(pyridin-3-yl)benzamido)isophthalic acid (H2PBI) to react with Mn(NO3)2 under solvothermal conditions, a 2-fold interpenetrated Mn-based metal-organic framework (Mn-PBI) with rutile-type topology has been obtained. When treated as a precursor by pyrolysis of Mn-PBI at 500 °C, mesoporous MnO/C-N nanostructures were prepared and treated as an lithium-ion battery anode. The MnO/C-N manifests good capacity of approximately 1085 mAh g-1 after 100 cycles together with superior cyclic stability and remarkable rate capacity, which is supposed to benefit from a large accessible specific area and unique nanostructures. The remarkable performances suggest promising application as an advanced anode material.

Molecular Insight into Assembly Mechanisms of Porous Aromatic Frameworks

The structural and dynamic factors governing porosity in porous aromatic frameworks (PAFs) are investigated using coarse-grained molecular dynamics simulations. PAFs form amorphous, porous networks with potential for gas storage and separation applications. We focus on a series of four PAFs—PAF-1, PPN-1, PPN-2, and PPN-3—which exhibit an unexpected trend in porosity as the structure of the PAF monomer is varied. The simulations suggest that nonbonding dispersion interactions that stabilize misbound monomer configurations play an essential role in the formation of porosity-reducing interpenetrated frameworks in PAFs comprising the larger PPN-1 and PPN-2 monomers; on the other hand, the simulations indicate that the steric bulk of a key reaction intermediate acts to limit interpenetration in PAFs made up of the smaller PAF-1 and PPN-3 monomers. The simulations also show that the rate of cluster growth, which depends largely on the monomer concentration used in the experimental synthesis, is significantly higher for PPN-1 and PPN-2, which would exacerbate the kinetic trapping of interpenetrated misbound configurations. This work provides design rules for synthesizing highly porous amorphous networks through the choice of monomer structure and reaction conditions that limit framework interpenetration.

Visible-light-driven photocatalysts of three nickel(II) coordination polymers with mixed ligands

Three ternary mixed-ligand Ni(II) coordination polymers (CPs) including {[Ni(DCTP)(L1)·(H2O)2]·(H2O)}n (1), [Ni(DCTP)(L2)·(H2O)2] (2), and [Ni(DCTP)(L3)] (3) (L1=1,4-bis(benzimidazol-1-yl)-2-butene, L2=1,4-bis(imidazol-1-ylmethyl)benzene, L3=1,4-bis(5,6-dimethylbenzimidazol-1-ylmethyl)benzene, H2DCTP=2,5-dichloroterephthalic acid), have been synthesized with a hydrothermal technique and structurally characterized by single-crystal X-ray diffraction, infrared spectroscopy, powder X-ray diffraction, and thermogravimetric analysis. Both CPs 1 and 2 display 2D 4-connected sql sheets, CP 1 exhibits a 2D L3(9)2(4) water layer interconnected by hydrogen bonding interactions, CP 2 is further extended into a 3D supramolecular framework through O–H⋯O hydrogen bonding interactions. CP 3 reveals a 3D 3-fold interpenetrated 4-connected dia framework with the point symbol {66}. Crystal packing analysis well indicates that O–H⋯O and C–H⋯ π are the most intermolecular interactions in CPs 1–2. Furthermore, the electrochemical properties of CPs 1–3 were discussed in detail. Notably, CPs 1–3 represented the rare examples of Ni(II) CPs materials as visible-light-driven photocatalysts and showed high activities for degradation of Methyl Blue.

Zinc(II) and cadmium(II) coordination polymers containing phenylenediacetate and bis(imidazol-1-ylmethyl)benzene linkers: The effect of ligand isomers on the solid state structures

This work presents a systematic investigation of the reactions of o-, m- and p-phenylenediacetic acid with Zn(II)/Cd(II) salts in the presence of different semi-rigid o-, m- and p-bis(imidazol-1-ylmethyl)benzene co-ligands. Fourteen new coordination polymers – {[Zn(μ-opda)(µ-mbix)]·0.5H2O}n (1), {[Zn(μ-mpda)(µ-obix)]·H2O}n (2), {[Zn2(μ-mpda)2(μ-mbix)2]·5H2O}n (3), {[Zn(μ-mpda)(µ-mbix)]·2H2O}n (4), {[Zn(μ-mpda)(µ-pbix)]·0.5H2O}n (5), [Zn(μ-ppda)(μ-obix)]n (6), {[Zn(μ-ppda)(µ-mbix)]·0.5H2O}n (7), {[Zn(μ-ppda)(μ-pbix)]·H2O·DMF}n (8), {[Cd(μ-mpda)(μ-obix)1.5]·H2O}n (9), {[Cd(μ-mpda)(μ-obix)]·H2O}n (10), {[Cd(μ-mpda)(μ-mbix)(H2O)]·H2O}n(11), [Cd(μ3-ppda)(µ-obix)]n (12), [Cd(μ3-ppda)(µ-mbix)]n (13) and [Cd(μ3-ppda)(µ-pbix)]n (14) (o/m/ppda=1,2/1,3-/1,4-phenylenediacetate, o/m/pbix=1,2-/1,3-/1,4-bis(imidazol-1-ylmethyl)benzene) – have been prepared and structurally characterized. Two of the complexes were found to possess one-dimensional (1D) structures, eleven complexes were found to be two-dimensional (2D) coordination networks and one of the complexes was found to be a three-dimensional (3D) coordination network. Of the 1D structures, 3 forms nanotubes, whereas in 8 pairs of pbix ligands bridge the zinc(II) centers to generate Zn2(pbix)2 dimers, which in turn are linked together by pairs of ppda linkers to give chains. Compound 5 contains a 4-fold interpenetrated 3D framework. The structure of 10 contains interpenetrated 2D frameworks, leading to a three-dimensional gross structure. The thermal stabilities and luminescent properties for 1–14 are also reported.

Interpenetrated Metal–Organic Frameworks of Cobalt(II): Structural Diversity, Selective Capture, and Conversion of CO2

Three new metal–organic frameworks (MOFs) of Co(II), [{Co(muco)(bpa)(2H2O)}·2H2O]n (1), [{Co(muco)(azopy)}·H2O]n (2), and [{Co(muco)(4bpdp)}·2DMF·H2O]n (3) (where, muco = trans, trans-muconate dianion, bpa = 1,2-bis(4-pyridyl)ethane, azopy = 4,4′-bisazobipyridine, and 4bpdb = 1,4- bis(4-pyridyl)-2,3-diaza-1,3-butadiene) have been synthesized and structurally characterized by single-crystal X-ray diffraction analysis. Structural analysis revealed that MOF1 exhibits an interesting 3-fold interpenetrated three-dimensional (3D) pillar-layered framework structure with 4-c, {66} topology, while 2 and 3 possess a 2-fold interpenetrated 3D pillar-layered framework structure with 7-c, {3∧3.4∧13.5∧4.6} net topology. Gas adsorption study of the compounds shows that 1 exhibits selective adsorption of CO2 over other (H2, N2, and Ar) gases with an uptake higher than those of 2 and 3. Further, the metal coordinated water molecules in MOF1 can be reversibly removed by high temperature treatment to generate a dehydrated f...

Siloxane-based linkers in the construction of hydrogen bonded assemblies and porous 3D MOFs.

A siloxane-based hexacarboxylic acid (L1-H6) has been prepared and applied in MOF construction. L1-H6 itself crystallizes as an unusual interpenetrated 3D hydrogen-bonded framework. Reaction of L1-H6 with Zn(ii) gave IMP-18 - a 3D MOF incorporating Si-O-Si functionality. Cleavage of L1-H6 gives a silanol-based triacid which is shown to give a coordination polymer (IMP-19) with Zn(ii).

Synthesis, structure and luminescence properties of two Cd(ii)/M(i) (M = K, Rb) interpenetrated heterometallic frameworks based on giant double-walled cages

Two isostructural 2-fold interpenetrated double-walled frameworks based on a rare heterometallic nested cage-within-cage motif were synthesized.

Expanding the Group of Porous Interpenetrated Zr-Organic Frameworks (PIZOFs) with Linkers of Different Lengths.

A Zr-based MOF of the PIZOF type, which consists of two independent and mutually interpenetrating UiO-type frameworks with [Zr6O4(OH)4(O2C)12] nodes, does not only form with a PEPEP dicarboxylic acid (P = phenylene, E = ethynylene). Also dicarboxylic acids with the shorter PPPP and PEPP spacers were found to give PIZOFs, denoted PPPP-PIZOF and PEPP-PIZOF, respectively. Reducing the spacer length even further to a PEEP segment caused a switchover to the formation of a UiO framework. The hysteresis in the Ar sorption curve of PEPP-PIZOF-1 and the slightly too large amount of combustion residue from PPPP-PIZOF-1 suggest structural defects. These hint at a mismatch between the requirement of the optimal linker length for PIZOF formation and the lengths of the PEPP and PPPP dicarboxylates. Nevertheless, these dicarboxylates prefer the formation of a PIZOF over the formation of a UiO structure. PEPEP-PIZOF-2, PPPP-PIZOF-1, and PEPP-PIZOF-1 are stable in air up to 325, 350, and 300 °C, respectively, and have BET surface areas of 2350, 2020, and 1650 m2 g-1, respectively. PEPEP-PIZOFs, even those with very hydrophilic oligo(ethylene glycol) side chains on the linkers, are very stable in water and also during drying from a water-wetted state. On the contrary, PEPP-PIZOF-1 and PPPP-PIZOF-1 that had been exposed to water required exchange of water for ethanol before drying to mostly preserve the framework. The results emphasize the importance of differentiating between framework damage caused through hydrolysis in water and through drying from a water-wetted state. The sensitivity of PEPP-PIZOF-1 and PPPP-PIZOF-1 against drying from a water-wetted state may be the consequence of defects. The drying stability of water-wetted PEPEP-PIZOFs lets us suggest that reversible bending of the linkers contributes to the stability of the PEPEP-PIZOFs.

Thermally Induced Intra‐Carboxyl Proton Shuttle in a Molecular Rack‐and‐Pinion Cascade Achieving Macroscopic Crystal Deformation

AbstractProton transport via dynamic molecules is ubiquitous in chemistry and biology. However, its use as a switching mechanism for properties in functional molecular assemblies is far less common. In this study, we demonstrate how an intra‐carboxyl proton shuttle can be generated in a molecular assembly akin to a rack‐and‐pinion cascade via a thermally induced single‐crystal‐to‐single‐crystal phase transition. In a triply interpenetrated supramolecular organic framework (SOF), a 4,4′‐azopyridine (azpy) molecule connects to two biphenyl‐3,3′,5,5′‐tetracarboxylic acid (H4BPTC) molecules to form a functional molecular system with switchable mechanical properties. A temperature change reversibly triggers a molecular movement akin to a rack‐and‐pinion cascade, which mainly involves 1) an intra‐carboxyl proton shuttle coupled with tilting of the azo molecules and azo pedal motion and 2) H4BPTC translation. Moreover, both the molecular motions are collective, and being propagated across the entire framework, leading to a macroscopic crystal expansion and contraction.

Thermally Induced Intra-Carboxyl Proton Shuttle in a Molecular Rack-and-Pinion Cascade Achieving Macroscopic Crystal Deformation.

Proton transport via dynamic molecules is ubiquitous in chemistry and biology. However, its use as a switching mechanism for properties in functional molecular assemblies is far less common. In this study, we demonstrate how an intra-carboxyl proton shuttle can be generated in a molecular assembly akin to a rack-and-pinion cascade via a thermally induced single-crystal-to-single-crystal phase transition. In a triply interpenetrated supramolecular organic framework (SOF), a 4,4'-azopyridine (azpy) molecule connects to two biphenyl-3,3',5,5'-tetracarboxylic acid (H4 BPTC) molecules to form a functional molecular system with switchable mechanical properties. A temperature change reversibly triggers a molecular movement akin to a rack-and-pinion cascade, which mainly involves 1) an intra-carboxyl proton shuttle coupled with tilting of the azo molecules and azo pedal motion and 2) H4 BPTC translation. Moreover, both the molecular motions are collective, and being propagated across the entire framework, leading to a macroscopic crystal expansion and contraction.

Two novel molybdenum-oxide-based organic-inorganic hybrid frameworks exhibiting twofold interpenetrated hms networks

Two novel polyoxometalate (POM)-based organic–inorganic hybrids, namely, [(CH3)2NH2][Co(tpba)(Mo2O7)]·2H2O (1) and [(CH3)2NH2][Ni(tpba)(Mo2O7)]·2H2O (2) (tpba=4-([4,2′:6′,4′′-terpyridin]-4′-yl)benzoic acid), have been synthesized and characterized by elemental analyses, IR spectra, TG analyses and single-crystal X-ray diffraction. Compounds 1 and 2 are isostructural and feature microporous interpenetrated frameworks, which are constructed from metal–organic layers pillared by the [Mo2O7]2− anions. Topologically, the overall structures of 1 and 2 can be classified as a rare (3,5)-connected twofold interpenetrated hms net, which has never been observed in POM-based hybrid materials prior to this work. Furthermore, the magnetic property of compound 1 are discussed.

ChemInform Abstract: Finely Tuning MOFs Towards High‐Performance Post‐Combustion CO2 Capture Materials

AbstractReview: 117 refs.

Four calcium(ii) coordination polymers based on 2,5-dibromoterephthalic acid and different N-donor organic species: syntheses, structures, topologies, and luminescence properties

By using different N-donor organic species as additional auxiliary ligands with structure-directing roles, four three-dimensional (3D) calcium-based coordination complexes, [Ca(dbt)(H2O)]n1, [Ca(H-dbt)2(5,5′-dmbpy)2]n2, (4,4′-bpy)0.5[Ca(dbt)(H2O)2]n3, and (H2-dib)[Ca3(dbt)4(H2O)4·2H2O]n4 (H2-dbt = 2,5-dibromoterephthalic acid, 2,2′-bpy = 2,2′-bipyridine, 5,5′-dmbpy = 5,5′-dimethyl-2,2′-bipyridine, 4,4′-bpy = 4,4′-bipyridine, dib = 1,4-di(1H-imidazol-1-yl)benzene), have been successfully synthesized under similar solvothermal conditions and structurally characterized. The organic amine molecules play different roles in the formation of four different metal–organic skeletons with diverse structural topologies, in which complexes 1–3 are neutral, and 4 comprises a negatively charged framework with diprotonated dib as the counterion. Complex 1 features a 3D (6,6)-connected framework structure composed of edge-sharing 1D Ca–O–Ca inorganic chains and dbt ligands. The 2,2′-bpy molecule plays an important role in the synthesis of 1 as the structure-directing agent (SDA). Complex 2 shows a 3D 2-fold interpenetrated diamondoid framework (dia, 66) formed by single metal nodes via linear H-dbt anions and bidentate chelating 5,5′-dmbpy ligands, while complex 3 exhibits a 3D noninterpenetrated pcu network with {412·63} topology constructed from binuclear [Ca2(CO2)4] secondary building units and two types of dbt ligands, in which 4,4′-bpy molecules are ordered within the 3D neutral calcium-based framework as template and space filling agents. Complex 4 is a unique (4,4,4,4,5)-connected 5-nodal topology net, in which the diprotonated dib molecules provide space filling to balance the negatively charged framework. In addition, the thermal stability and the fluorescence properties of complexes 1–4 have been investigated.

Three-Dimensional Metal-Catecholate Frameworks and Their Ultrahigh Proton Conductivity.

A series of three-dimensional (3D) extended metal catecholates (M-CATs) was synthesized by combining the appropriate metal salt and the hexatopic catecholate linker, H6THO (THO(6-) = triphenylene-2,3,6,7,10,11-hexakis(olate)) to give Fe(THO)·Fe(SO4) (DMA)3, Fe-CAT-5, Ti(THO)·(DMA)2, Ti-CAT-5, and V(THO)·(DMA)2, V-CAT-5 (where DMA = dimethylammonium). Their structures are based on the srs topology and are either a 2-fold interpenetrated (Fe-CAT-5 and Ti-CAT-5) or noninterpenetrated (V-CAT-5) porous anionic framework. These examples are among the first catecholate-based 3D frameworks. The single crystal X-ray diffraction structure of the Fe-CAT-5 shows bound sulfate ligands with DMA guests residing in the pores as counterions, and thus ideally suited for proton conductivity. Accordingly, Fe-CAT-5 exhibits ultrahigh proton conductivity (5.0 × 10(-2) S cm(-1)) at 98% relative humidity (RH) and 25 °C. The coexistence of sulfate and DMA ions within the pores play an important role in proton conductivity as also evidenced by the lower conductivity values found for Ti-CAT-5 (8.2 × 10(-4) S cm(-1) at 98% RH and 25 °C), whose structure only contained DMA guests.

Single-Crystal to Single-Crystal Linker Substitution, Linker Place Exchange, and Transmetalation Reactions in Interpenetrated Pillared-Bilayer Zinc(II) Metal-Organic Frameworks.

A twofold interpenetrated pillared-bilayer framework, {[Zn3 (L)2 (L2 )(DMF)]⋅(18DMF)(6H2 O)}n (1), has been synthesized from the ligands tris(4'-carboxybiphenyl)amine (H3 L) and 1,2-bis(4-pyridyl)ethylene (L2 ). The structure contains [Zn3 (COO)6 ] secondary building units (SBUs), in which three Zn(II) ions are almost linear with carboxylate bridging. This framework undergoes reversible pillar linker substitution reactions at the terminal Zn(II) centers with three different dipyridyl linkers of different lengths to afford three daughter frameworks, 2-4. Frameworks 2-4 are interconvertible through reversible linker substitution reactions. Also, competitive linker-exchange experiments show preferential incorporation of linker L3 in the parent framework 1. The larger linker L5 does not undergo such substitution reactions and framework 5, which contains this linker, can be synthesized solvothermally as a twofold interpenetrated structure. Interestingly, when framework 5 is dipped in a solution of L3 in DMF, linker substitution takes place as before, but linker L5 now moves and diagonally binds two Zn(II) centers to afford 6 as a nonpenetrated single framework. This linker place exchange reaction is unprecedented. All of these reactions take place in a single-crystal to single-crystal (SC-SC) manner, and have been observed directly through X-ray crystallography. In addition, each 3D framework undergoes complete copper(II) transmetalation.

Porous Cd-carboxylate frameworks tuned by the bulk of linker: Interpenetrated nets, selective CO2 uptakes and high water vapor adsorption

Reported herein are two porous interpenetrated anionic Cd-carboxylate frameworks tuned by the length of organic linker. Shorter BDC linker and [Cd(COO)4] building blocks in 1 generate a rare 4-connected 2-fold interpenetrating qtz network. But longer NDC linker in 2 produces a self-penetrated 8-connected bcu framework with [Cd3(COO)8] SBUs. 1 and 2 both show selective CO2 adsorption and significantly, 2 exhibits the highest water vapor uptake performance (281cm3·g−1 at 298K and P/P0=0.95) among all the interpenetrated MOFs.