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Metal–organic frameworks (MOFs) as types of proton conductive materials have attracted much attention. Here, an acylamide-functionalized 3D MOF, [Ni3(TPBTC)2(stp)2(H2O)4]·2DMA·32H2O, has been successfully constructed via combining Ni(NO3)2, TPBTC (TPBTC = benzene-1,3,5-tricarboxylic acid tris-pyridin-4-ylamide) and 2-H2stp (2-H2stp = 2-sulfoterephthalic acid monosodium salt) under solvothermal conditions. Single-crystal X-ray diffraction revealed that there are uncoordinated guest DMA molecules in the pores of the compound. On removal of guest DMA molecules, the proton conductivity of the compound increased to 2.25 × 10−3 S cm−1 at 80 °C and 98% RH which is about 110 times that of the original material. It is hoped that this work can provide essential insight for designing and obtaining improved crystalline-state proton conducting materials by considering the influences of guest molecules on proton conduction properties of porous materials. [ABSTRACT FROM AUTHOR]

The first CB[6]-based 3D porous metal–organic rotaxane framework is constructed by the reaction of CuCl2, terephthalic (H2BDC) and CB[6]-based [2]pseudorotaxanes ([PR44]2+·2[PF6]−) under solvothermal conditions. The structure of MORF-1 is a pillared-layer structure with 5-connected sqp topology, in which the effective free volume is 45.4% of the crystal volume. The guest molecules exchange in a single-crystal-to-single-crystal fashion, which was investigated using NMR spectroscopy and X-ray crystallography. [ABSTRACT FROM AUTHOR]

Three new compounds, [Cu(bimb)]2(HPW12O40)·3H2O (1), (H2bimb)2SiW12O40(2) and (H2bimb)3CoW12O40(3) (bimb = 1,4-bis(imidazol-1-ylmethyl)biphenyl), have been synthesized under the same hydrothermal conditions. Structural characterizations by single-crystal X-ray diffraction show that compound 1possesses a porous metal–organic pseudo-rotaxaneframework in which [PW12O40]3−clusters are encapsulated, whereas compounds 2and 3are common supramolecular compounds. The distinct structure of compound 1suggests that the porous framework may selectively encapsulate the polyoxometalate clusters, although the three polyoxometalate clusters have subtle structural differences. Catalytic photodegradation of organic dye RhB by compounds 1–3has been studied. [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]

Two POM-pillared 3D porous compounds, [CuICuII(CuIIfcz)2(H2O)5(PMoVI10MoV2O40)]·6H2O (1) and [CuI2(CuIIfcz)2(H2O)2(PMoVI8VV3VIV3O42)]·6H2O (2) (Hfcz = fluconazole, (1-(2,4-difluorophenyl)-1,1-bis[(1H-1,2,4-triazol-1-yl)methyl]benzyl alcohol) have been constructed based on different polyanions, (Cufcz)22+ macrocations and copper cations by the hydrothermal method. The (Cufcz)22+ macrocations link Cu cations to generate a 2D wavelike cationic sheet. Then the POM anions act as pillars to the cationic sheet to form different POM-pillared 3D frameworks. In compound 1, the polyanion exhibits a rare coordination mode and acts as a penta-dentate ligand, which acts as to pillars to the cationic sheet to form an unprecedented 3D (3,4,5,6)-connected open framework with (3·6·7)(32·6·73)(33·4·62·73·8)(34·42·62·76·8)(32·62·76·84·10) topology. In compound 2, polyanions covalently link cationic sheets to extend to an unusual 3D (3,4,6)-connected framework with the (52·6)(52·62·7·9)(54·64·74·93) topology. To the best of our knowledge, it is the first time that POM-pillared 3D metal–organic frameworks have been realized by combining POMs with deliberately designed macrocations and transition-metal ions, using a rational approach for synthesis of POM-based open metal–organic frameworks. In addition, the electrochemical behaviors of compounds 1 and 2 have been investigated. [ABSTRACT FROM AUTHOR]

The hematite nanorods and magnetite nanoparticles were synthesized via direct thermolysis of an iron-based metal-organic framework materials MIL-100(Fe) (MIL: Materials of Institut Lavoisier) for the first time and used as absorbents for the removal of As(V). The prepared materials were characterized by XRD, SEM, TEM and BET. It was found that calcination temperature and calcination atmosphere affected the pore sizes and types of the obtained materials, and then further influenced the removal of As(V). At pH 3, the As(V) adsorption capacities of obtained Fe3O4 and α-Fe2O3 calcined at 350 °C, 550 °C, 750 °C were 80.5 mg g-1, 94.9 mg g-1, 74.1 mg g-1 and 70.5 mg g-1, respectively. This approach may provide reference for the synthesis of other metal oxide nanoparticles. [ABSTRACT FROM AUTHOR]

Two S-containing MOFs, interpenetrating IFMC-27 and non-interpenetrating IFMC-28, were synthesized by altering solvent size. The nanoporous IFMC-28 reveals high selective adsorption for Cu2+ ions and has been applied as a chromatographic column for separating transition metal ions for the first time. [ABSTRACT FROM AUTHOR]

A novel compound, [Cu(bimb)]2(HPW12O40)·3H2O (bimb = 1,4-bis(imidazol-1-ylmethyl)biphenyl) with a polyoxometalate-encapsulated 3D metal–organic pseudo-rotaxaneframework that can be described as a 2-fold dianet topology showing well-defined 1D nano-scale tunnels, has been synthesized hydrothermally, and its de-/rehydration behavior has been investigated. [ABSTRACT FROM AUTHOR]

Abstract: Nanoporous manganese was fabricated by a three-step process involving high power laser cladding of a homogeneous Cu40Mn60 alloy coatings onto a mild steel substrate, laser remelting for tuning the grain size and the composition homogeneity followed by selectively electrochemical de-alloying for removal of Cu element and formation of nanoporous Mn. The microstructure and homogeneity of the precursor Cu40Mn60 alloys have a significant influence on the evolution of nanopores during selectively electrochemical de-alloying. Laser remelting can significantly refine the microstructure. The second dendrite arm spacing decreases with increasing of laser remelting scanning speed. A SDAS of 1.17μm was obtained at the laser scanning speed of 133mm/s. When the remelting scanning speed reaches 100mm/s, a nanoporous structure with average pore size less than 100nm was achieved under optimized dealloying electrode current density about 2mA/cm2. Nanoporous Mn with nanopore sizes ranging from 80 to 130nm was fabricated by this method. Surface-enhanced Raman scattering characteristics of the nanoporous materials have been investigated. It is found that smaller nanoporosity leads to significant improvements in surface-enhanced Raman scattering. [ABSTRACT FROM AUTHOR]

Abstract A novel porous coordination polymer compound [Cd 0.5 (tpy)]∙0.75H 2 O was prepared by hydrothermal synthesis, which exhibits excellent chemical stability under various organic solvents and aqueous solution with different pH values range from 3 to 13. Benefiting from guest water molecules existing in the crystal structure, this compound shows water-mediated proton (H+) ion-conducting with conductivity of 6.03 × 10−6 S·cm−1 under 97% relative humidity at 95 °C. The calculated thermal activation energy (1.09 eV) and strong dependency on the humidity indicates a vehicle mechanism in the proton conduction process. Graphical abstract A water molecules contained porous coordination polymers with excellent chemical and thermal stability was reported which shows water-mediated proton (H+) ion-conducting property with vehicle mechanism. Unlabelled Image Highlights • A novel porous coordination polymer compound (1) with guest water molecules in pores was prepared. • Compound 1 exhibits excellent chemical stability under organic solvents and aqueous solution with different pH values. • 1 shows water-mediated proton (H+) ion-conducting with conductivity of 6.03 × 10−6 Scm−1 under 97% relative humidity at 95 °C. [ABSTRACT FROM AUTHOR]

A novel metal-organic framework (MOF) with a π-conjugated porous condition is reported to sensor fused aromatic hydrocarbons molecules. This MOF assembled by N-heterocyclic multi-carboxyl ligands and Cd ions shows hexagonal hydrophobic channels along [100] and [010] directions with size 18.4 × 15.5 Å 2 . Under the excitation of 338 nm, this MOF emits blue light peaking at 397 nm. Under immersing this MOF in the solutions containing aromatic hydrocarbon, including naphthalene, anthracene and phenanthrene within different time, the luminescent intensity of MOF enhanced different degree upon encapsulating aromatic hydrocarbons guest molecules. Therefore, this material shows favourable property of recognition for aromatic hydrocarbons molecules via solid-state photoluminescence. [ABSTRACT FROM AUTHOR]

Abstract: A new porous 2D metal–organic framework [Cu(L)DMF]·2H2O (1) has been synthesized by self-assembling copper paddle-wheel units with an asymmetrical dicarboxylate ligand prolonged by alkyne groups, 3,3′-(ethyne-1,2-diyl)dibenzoic acid (H2L) under solvothermal condition. The activated sample 1a displays selective adsorption of CO2 over N2 and shows low isosteric heat (Q st) of CO2 adsorption. [Copyright &y& Elsevier]

Synopsis: Novel two dimensional TM-C(CN) 3 (TM = Sc ∼ Zn) monolayers within specific TMN 3 active sites possess excellent electrocatalytic CO 2 reduction activity and selectivity. [Display omitted] • The TM-C(CN) 3 monolayers are constructed by embedded TM atoms in periodic g-C(CN) 3 cell. • The Sc-, Co–, and Ni-C(CN) 3 monolayers are screened out from 10 TM-C(CN) 3 monolayers to be promising single-atom-catalysts for CO 2 RR with the low limiting potentials. • This work sheds light on g-C(CN) 3 monolayer as an excellent supporting material, and will motivate more experimental and theoretical researches to further explore other potential two-dimensional porous carbon-based materials. Electrochemical reduction of CO 2 (CO 2 RR) represents a fascinating route for converting atmospheric CO 2 to valuable chemicals, and a variety of intermediates are involved in the different CO 2 RR pathways. However, it has been hampered by the lack of highly effective electrocatalysts so far. Here, the performance of single 3d non-precious transition metals supported on g-C(CN) 3 monolayers [TM-C(CN) 3 , TM = Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, respectively] as CO 2 RR electrocatalysts was systematically investigated by using density functional theory (DFT) calculations. The data indicate that all these TM atoms can strongly interact with the g-C(CN) 3 substrate, and the TM active sites possess high CO 2 RR activity and specific selectivity through *OCHO intermediate. Particularly, Sc-, Co–, and Ni-C(CN) 3 monolayers are identified as effective CO 2 RR electrocatalysts due to the low limiting potentials (- 0.28, − 0.42, and − 0.46 V, respectively), whose excellent performances are mainly attributed to the specific TMN 3 active sites. Therefore, this work sheds light on g-C(CN) 3 monolayer as an excellent supporting material, and will motivate more experimental and theoretical researches to further explore other potential two-dimensional porous carbon-based materials with specific TMN 3 active sites for CO 2 RR. [ABSTRACT FROM AUTHOR]

Abstract: Three metal–organic frameworks (MOFs), [Co2(BPDC)2(4-BPH)·3DMF] n (1), [Cd2(BPDC)2(4-BPH)2·2DMF] n (2) and [Ni2(BDC)2(3-BPH)2 (H2O)·4DMF] n (3) (H2BPDC=biphenyl-4,4′-dicarboxylic acid, H2BDC=terephthalic acid, BPH=bis(pyridinylethylidene)hydrazine and DMF=N,N′-dimethylformamide), have been solvothermally synthesized based on the insertion of heterogeneous BPH pillars. Framework 1 has “single-pillared” MOF-5-like motif with inner cage diameters of up to 18.6Å. Framework 2 has “double pillared” MOF-5-like motif with cage diameters of 19.2Å while 3 has “double pillared” 8-connected framework with channel diameters of 11.0Å. Powder X-ray diffraction (PXRD) shows that 3 is a dynamic porous framework. [Copyright &y& Elsevier]

Abstract: Three coordination polymers, i.e. [Co(HL)(HBDC)]n (1), [Co(HL)(BDC)0.5]n (2) and {[Zn2(H2L)(BTC)2](H4L)(H2O)2}n (3) (L=2, 2′-(ethanediyl)bis(1H-benzimidazole), H2BDC=1, 4-benzenedicarboxylic acid, H3BTC=1, 3, 5-benzene tricarboxylic acid), have been synthesized under hydrothermal conditions based on bis(2-benzimidazole) and two multi-dentate carboxylate ligands, with different metal ions such as ZnII and CoII. The structures of these coordination polymers have been determined by X-ray single‐crystal diffraction. The diverse coordination modes of the H2L ligand and the varying geometries of multi-dentate carboxylate ligands play an important role in the construction of coordination polymers. Various assembly patterns have been observed, including one-dimensional (1D) chain (1), two-dimensional (2D) 3-connected network structure with honeycomb topology (2), and three-dimensional (3D) 3,4-connected porous structure with (63)(65,8) topology (3). Thermal analyses of the three polymers have been performed and discussed. Furthermore, strong room temperature photoluminescence of compound 3 was observed. [Copyright &y& Elsevier]

Abstract: The functionalization of porous metal–organic frameworks (Cu3(BTC)2) was achieved by incorporating Keggin-type polyoxometalates (POMs), and further optimized via alkali metal ion-exchange. In addition to thermal gravimetric analysis, IR, single-crystal X-ray diffraction, and powder X-ray diffraction, the adsorption properties were characterized by N2 and volatile organic compounds (VOCs) adsorption measurements, including short-chain alcohols (C<4), cyclohexane, benzene, and toluene. The adsorption enthalpies estimated by the modified Clausius–Clapeyron equation provided insight into the impact of POMs and alkali metal cations on the adsorption of VOCs. The introduction of POMs not only improved the stability, but also brought the increase of adsorption capacity by strengthening the interaction with gas molecules. Furthermore, the exchanged alkali metal cations acted as active sites to interact with adsorbates and enhanced the adsorption of VOCs. [Copyright &y& Elsevier]

Abstract: A non-interpenetrated 3D porous metal–organic framework [(CH3)2NH2]2[Cd(TATAT)2/3]·4DMF (1) (TATAT=5,5′,5″-(1,3,5-triazine-2,4,6-triyl)tris(azanediyl)triisophthalate) has been successfully synthesized under solvothermal conditions and characterized by elemental analysis, TGA, and single-crystal X-ray diffraction analysis. Compound 1 exhibits α-Al2O3 (corundum) topology and represents the first metal–organic analog presently known with a natural material topology based on 6-connected organic ligand and tetrahedral metal ion. In addition, the thermal stabilities of the complex and the acid-treated product have been investigated and the results indicate that acid treatment is an efficient way for this compound to improve its thermal stability. [Copyright &y& Elsevier]