A novel Zn-based metal–organic framework (MOF) was synthesized from the mixed ligands, 3,3′,5,5′-azoxybenzenetetracarboxylic acid (H4AOBTC) and 1,4-bis(1H-benzo[d]imidazol-1-yl)benzene (phenDIB) ligand. The crystal structure of the complex exhibits an interpenetrated three-dimensional framework that can be simplified as a (4,4)-connected 2-nodal bbf net. This MOF displays extraordinary thermostability in boiling water for 12 h and chemical stability in a wide pH range of 2–13. The most intriguing feature is that it can successfully separate cationic dyes from mixed dye molecules in aqueous solution with high effectivity and selectivity, even for rhodamine B molecule with a large size. Furthermore, this material is reusable, and the adsorbed dye molecules can be released and recovered completely. It is very important for the practical application from a view of environmental protection and resource recycling.

The in situ growth of Bi-based metal–organic framework (MOF) (CAU-17) on BiOBr 2D material was prepared for the first time by using a facile solvothermal transformation approach. The BiOBr was applied both as template to support the growth of MOF and as Bi3+ source of MOF. The BiOBr/CAU-17-2h composite exhibited enhanced photocatalytic activity for degradation of Rhodamine B (RhB), methylene blue (MB), and methyl orange (MO) under visible light irradiation, suggesting a good synergy between BiOBr and CAU-17 MOF.

•Ultrathin NiO nanosheets were coated on hollow N-doped carbon spheres with the assistance of polydopamine.•The hierarchical hollow nanostructures have high surface area and uniform pore size distribution.•HNCS-NiO nanocomposites exhibit high capacitance of 550.4 F g− 1 at the current density of 0.5 A g− 1.The polydopamine-assisted hierarchical composites of ultrathin NiO nanosheets uniformly coating on the surface of hollow nitrogen-doped carbon spheres (HNCS-NiO) were successfully fabricated via a facile synthesis method. The hierarchical HNCS-NiO composites as electrode materials for supercapacitors exhibit high capacitance of 550.4 F g− 1 (880.6 mF cm− 2) at the current density of 0.5 A g− 1 (0.8 mA cm− 2), and present a good rate capability. The composites display excellent improved electrochemical properties not only because their hierarchical hollow nanostructures can provide enough space to buffer the volume expansion during the reversible intercalation/deintercalation processes, but also because their larger specific surface areas can provide adequate active sites for the redox electrochemical reaction.The polydopamine-assisted hierarchical composites of ultrathin NiO nanosheets uniformly coating on the surface of hollow nitrogen-doped carbon spheres were fabricated, which exhibit excellent electrochemical properties as electrode materials for supercapacitors.Download high-res image (113KB)Download full-size image

A hierarchical NiO/NiMn-LDH nanosheet array on Ni foam was prepared via a facile two-step approach and exhibited a high specific capacitance (937 F g−1 at 0.5 A g−1) and good cycling stability (91% retention after 1000 cycles at 5 A g−1). The improved electrochemical performance is benefited from the synergistic properties of hierarchical NiO/LDH nanosheet composites on a conductive substrate.

We present the use of silica-polydopamine (SiO2@PDA) core–shell nanoparticles (NPs) as self-confined templates for the fabrication of ultra-stable hollow Pt anchored N-doped carbon nanospheres (Pt/HN-C). SiO2@PDA nanospheres were fabricated by a facile one-pot process, followed by the deposition of Pt NPs onto the outer shell layer. The confinement and adhesion of the PDA framework ensured the distribution and stability of Pt NPs after carbonization at the carbon shell layer. The converted Pt/HN-C exhibited excellent catalytic performance and durability for the oxygen reduction reaction (ORR).

Electrode materials for supercapacitors with one-dimensional porous nanostructures, such as nanowires and nanotubes, are very attractive for high-efficiency storage of electrochemical energy. Herein, ultralong Cu-based porous coordination polymer nanowires (copper-L-aspartic acid) were used as the electrode material for supercapacitors, for the first time. The as-prepared material exhibits a high specific capacitance of 367 F g−1 at 0.6 A g−1 and excellent cycling stability (94% retention over 1000 cycles). Moreover, porous CuO nanotubes were successfully fabricated by the thermal decomposition of this nanowire precursor. The CuO nanotube exhibits good electrochemical performance with high rate capacity (77% retention at 12.5 A g−1) and long-term stability (96% retention over 1000 cycles). The strategy developed here for the synthesis of porous nanowires and nanotubes can be extended to the construction of other electrode materials for more efficient energy storage.

To explore catalysts combining highly accessible specific surface areas with low recombination of the photo-induced electron–hole pairs, a novel SiO2@PDA@BiOBr composite photocatalyst with a hierarchical core–shell structure was prepared by a facile solvothermal method. The catalyst shows a superior performance on photodegradation of Rhodamine B under visible light irradiation, especially for SiO2@PDA-2@BiOBr with the reactant kinetics constant (k = 0.0487 min−1). The enhanced photocatalytic performance of SiO2@PDA-2@BiOBr was ascribed to the decreased band-gap, higher surface area, and effectively photo-generated electron–hole pairs by the introduction of polydopamine (PDA). In addition, the photocatalytic degradation is initiated by ˙O2− derived from dye photosensitization and h+ from the BiOBr. Cyclic experiments also indicate that the SiO2@PDA-2@BiOBr is reusable during the photodegradation process. The hierarchical core–shell SiO2@PDA@BiOBr photocatalyst will provide a theoretical model for the development of physical chemistry and structural properties of BiOBr-based composites to enhance the photocatalytic performances.

•A novel BiOBr/Bi24O31Br10/TiO2 heterostructure was achieved by calcining BiOBr/MIL-125(Ti) composite.•The heterostructure exhibited the photocatalytic performance for degradation of RhB.•The enhanced photocatalytic activity is attributed to synergistic effect between BiOBr, Bi24O31Br10 and TiO2.•This work could be conductive to the design of heterostructured photocatalysts by pyrolytic conversion of MOF.The pyrolysis of metal-organic frameworks has emerged as a promising route to synthesize metal oxides with diverse phase compositions, morphologies, sizes and surface areas. The BiOBr/Bi24O31Br10/TiO2 (BBT) heterostructures have been achieved for the first time by calcining BiOBr/MIL-125(Ti) composite at 500 °C in air. The BBT-2 composite exhibited the highest photocatalytic performance for degradation of RhB under visible light irradiation. The enhanced photocatalytic activity is attributed to narrower band-gaps and synergistic effect originating from the well-aligned straddling band-structures between BiOBr, Bi24O31Br10 and TiO2, also result in an faster interfacial charge transfer during the photocatalytic reaction. This work could be conductive to the design of heterostructured photocatalysts contained metal oxide by pyrolytic conversion of metal-organic frameworks for significantly improved photocatalytic performance.A novel BiOBr/Bi24O31Br10/TiO2 heterostructure was achieved by calcining BiOBr/MIL-125(Ti) composite and exhibited the photocatalytic performance for degradation of RhB.Download high-res image (249KB)Download full-size image

A multifunctional metal–organic framework, NBU-3, has been explored as a 2D three-connected network based on a naphthalenediimide-based ligand. The NBU-3 crystals display photochromic properties, and NBU-3 thin films on FTO substrates exhibit electrochromic properties. NBU-3 is the first example of MOF materials containing both photochromic and electrochromic properties, which can be desirable for thin film devices.

Nanorods-composed yolk–shell bimetallic-organic frameworks microspheres are successfully synthesized by a one-step solvothermal method in the absence of any template or surfactant. Furthermore, hierarchical double-shelled NiO/ZnO hollow spheres are obtained by calcination of the bimetallic organic frameworks in air. The NiO/ZnO hollow spheres, as supercapacitor electrodes, exhibit high capacitance of 497 F g−1 at the current density of 1.3 A g−1 and present a superior cycling stability. The superior electrochemical performance is believed to come from the unique double-shelled NiO/ZnO hollow structures, which offer free space to accommodate the volume change during the ion insertion and desertion processes, as well as provide rich electroactive sites for the electrochemical reactions.

A hexagonal nanosheet LDH@ZIF-8 composite was fabricated by in situ growth of ZIF-8 on Zn–Al LDH without adding any zinc precursor, and exhibited a CO2 adsorption capacity of 1.0 mmol g−1 at room temperature and 1 bar, which was significantly higher than that of pure Zn–Al LDH or ZIF-8, indicating a synergy between ZIF-8 and Zn–Al LDH.

•Cage-like Mo-KIT-5 with various Si/Mo ratios was prepared.•Mo-KIT-5 shows ordered mesoporous structure.•The superior textural property leads to high dispersion of active Mo species.•Mo-KIT-5 showed better activity than Mo/KIT-5 and Mo-SiO2.•Mo-KIT-5 is advantageous over Mo-SBA-15 and Mo-KIT-6.Molybdenum containing three-dimensional (3D) cage-like mesoporous KIT-5 (Mo-KIT-5) materials with various Si/Mo ratios was successfully prepared by one-pot hydrothermal synthesis. The obtained materials were characterized by various techniques, such as XRD, N2 physisorption, TEM, FTIR, UV-DRS, XPS, and NH3-TPD. Characterization results revealed that molybdenum species could be finely dispersed in the framework of KIT-5 without disturbing long-range ordering at Si/Mo ratios higher than 15, while collapse of mesoporous structure and presence of bulk MoO3 was observed for Mo-KIT-5-5 sample with a Si/Mo ratio of 5. Mo-contained materials were investigated in catalytic conversion of 1-butene and ethylene to propene. Among all of Mo-KIT-5 materials studied, Mo-KIT-5-40 with Si/Mo ratio of 40 exhibited best catalytic performance caused by the fact that it processed superior textural properties, substantial active Mo species, and appropriate amount of acidic sites. Further decreasing the Si/Mo ratio resulted in declined activity due to the presence of extraframework Mo species. It was found that doped Mo-KIT-5-40 showed better catalytic activity than control supported Mo/KIT-5-40 and Mo/SiO2-40 catalysts with same Mo loading due to the highly dispersed active Mo species on the mesoporous framework. Moreover, Mo-KIT-5 was also superior to other Mo containing mesoporous materials, such as Mo-SBA-15 with two-dimensional pores and Mo-KIT-6 with three-dimensional cylindrical pores, implying the advantage of this kind of ordered 3D cage-like mesoporous materials in this reaction.3D cage-like mesoporous Mo-KIT-5 displayed superior catalytic performance to conventional supported catalysts and other mesoporous catalysts.

A new multifunctional enantiopure ligand, (S)-2-(1,8-naphthalimido)-3-(4-imidazole)propanoate (s-nip), containing a homochiral center derived from l-histidine and a strong π···π stacking 1,8-naphthalimide synthon, has been used to prepare three novel metal–organic frameworks. The frameworks of [Zn(s-nip)2]n (1) and {[Co(s-nip)2]·(H2O)0.5}n (2) are isostructural three-dimensional (3D) homochiral supramolecular structures organized one-dimensional (1D) ribbons by strong hydrogen bonds and π···π interactions, which display ferroelectric behavior at room temperature. The complex [Cu(nia)2·(H2O)5]n (3) was constructed under a hydrothermal in situ ligand synthesis reaction, in which the new ligand 2-(1,8-naphthalimido)-3-(4-imidazole)acrylate (nia) was formed from the s-nip ligand via a dehydrogenation reaction. The two-dimensional network of 3 stacks into a 3D structure via π···π interactions resulting in 1D hydrophilic channels.

•A MOF microflowers were prepared from Co2+ and nicotinic acid.•Porous Co3O4 microflowers were obtained by calcinations the MOF precursors.•Porous Co3O4 electrode exhibits a specific capacitance of 240.2 F g−1 at a current density of 0.625 A g−1.•The specific capacitance of Co3O4 remains more than 96.3% after 2000 cycles at 3.75 A g−1.Porous Co3O4 microflowers were successfully synthesized by calcinations of novel flower-like metal-organic framework microcrystals. A supercapacitor was conducted based on this porous Co3O4 microflowers as the electrode material, which shows that the porous Co3O4 electrode exhibit a specific capacitance of 240.2 F g−1 at the current density of 0.625 A g−1 and remains more than 96.3% after 2000 cycles. The results demonstrate that porous Co3O4 microflowers can be acted as a promising electrode candidate in supercapacitors.

The ever-emerging demands on miniaturization of electronic devices have pushed the development of innovative materials with desired properties. One major endeavor is the development of organic- or organic–inorganic hybrid-based electronics as alternatives or supplements to silicon-based devices. Herein we report the first observation of the coexistence of resistance switching and ferroelectricity in a metal–organic framework (MOF) material, [InC16H11N2O8]·1.5H2O, denoted as RSMOF-1. The electrical resistance of RSMOF-1 can be turned on and off repeatedly with a current ratio of 30. A first-principles molecular dynamics simulation suggests that the resistive switching effect is related to the ferroelectric transition of N···H–O···H–N bridge-structured dipoles of the guest water molecules and the amino-tethered MOF nanochannel. The discovery of the resistive switching effect and ferroelectricity in MOFs offers great potential for the physical implementation of novel electronics for next-generation digital processing and communication.

•Two isomorphic 2D coordination polymers were prepared from benzophenone-4,4′-dicarboxylic acid.•The 2D layers display sinusoidal wavelike structures.•The topology of 2D structure is (3,4)-connected net forming 4 and 6-gons.•The Schläfli notation of 2D topology is (4·62)(42·62).Two isomorphic 2D metal–organic coordination polymers, [Zn(bpndc)(H2O)]∞ (1) and [Cd(bpndc)(H2O)]∞ (2), have been hydrothermally prepared by exploring a semi-rigid V-type dicarboxylate ligand, benzophenone-4,4′-dicarboxylic acid (H2bpndc). Two complexes were characterized by single crystal X-ray diffraction, elemental analyses, IR spectrum, powder X-ray diffraction, thermal analyses, UV–Vis and fluorescence emission spectra. The metal ions in 1 and 2 are connected by carboxylate groups of bpndc to generate a 1D chain with doubly helical structures. The chains are linked by bpndc to form a 2D sinusoidal wavelike layer, which are further assembled with O–H⋯O hydrogen bonds to generate a 3D supramoleclar networks. The topology of 2D structure is an unusual flat (3,4)-connected net forming 4 and 6-gons with the Schläfli notation of (4·62)(42·62) (see Natarajan and Mahata, 2009 [14]).Two isomorphic 2D sinusoidal wavelike coordination polymers display an unusual flat (3,4)-connected net forming 4 and 6-gons, which are further assembled with O–H⋯O hydrogen bonds to generate a 3D supramoleclar networks.

A doubly interpenetrated metal–organic framework, [Zn3(TATB)2(H2O)2]n (2), with chiral (10,3)-a topology, has been synthesized from an achiral, trigonal-planar ligand, 4,4′,4″-s-triazine-2,4,6-triyltribenzoate (TATB). The large chiral channels in 2 act as scaffolds for the inclusion of N,N-dimethylaniline (DMA) molecules by donor–acceptor interactions. The resulting host–guest composite, DMA@2, shows desirably intense luminescence, which originated from photoinduced charge-transfer interactions in excited states.

Two 3D noninterpenetrated pillar-layered metal–organic frameworks have been synthesized under solvothermal reactions based on a N,N′-di(4-pyridyl)-1,4,5,8-naphthalenetetracarboxydiimide (DPNDI) pillar. Single-crystal X-ray diffraction analyses revealed that compound [Co3(BDC)3(DPNDI)(DMF)2]·2CH3CN (1) displays an eight-connected hex net with Schläfli symbol 36·418·53·6 and consists of a DPNDI pillar and 2D 36 net layer that was constructed from a pinwheel trimetallic secondary building unit and 1,4-benzenedicarboxylate (BDC) linker. Compound [Zn2(HFIPBB)2(DPNDI)]·8DMF (2) exhibits a six-connected mab net with Schläfli symbol 44·610·8 and consists of a DPNDI pillar and 2D wavelike 44 net layer with helical channels that was constructed from a paddlewheel dimetallic secondary building unit and bent V-type 4,4′-(hexafluoroisopropylidene)bis(benzoate) linker. The phase purity, thermal stability, and N2 adsorption/desorption of 1 and 2 were measured; the antiferromagnetic property of 1 as well as the photochromic phenomenon of 2 have also been investigated and discussed.

Hydrothermal reactions of aromatic 3,3′,5,5′-biphenyltetracarboxylic acid (H4bpt) and the transitional metal cations in the presence of rigid or flexible N-donor ancillary ligands afford nine novel coordination polymers, namely, [M(H2bpt)(Hpptp)]n (M = Mn (1), Fe (2), Co (3), and Zn (4)), [Mn2(bpt)(Hpptp)2]n (5), {[Zn3(Hbpt)(bpt)(H2O)2][(4,4′-H2bmib)0.5]·H2O}n (6), {[Cu(bpt)0.5(4,4′-bimbp)]·H2O}n (7), {[Co(H2bpt)(2,7-dfo)]·H2O}n (8), and {[Ni2(bpt)(4,4′-bibp)2.5(H2O)]·3(H2O)}n (9) (Hpptp = 2-(3-(4-(pyridin-4-yl)phenyl)-1H-1,2,4-triazol-5-yl)pyridine; 4,4′-bmib = 4,4′-bis(2-methylimidazol-1-yl)benzene; 4,4′-bimbp = 4,4′-bis(imidazol-1-ylmethyl)biphenyl; 2,7-dfo = 2,7-di(imidazo-1-ly)-9H-fluoren-9-one; 4,4′-bibp = 4,4′-bis(imidazol)biphenyl). Their structures have been determined by single-crystal X-ray diffraction analyses, elemental analyses, IR spectra, powder X-ray diffraction (PXRD), and thermogravimetric (TG) analyses. Complexes 1–4 are isomorphism and feature a similar 2-fold interpenetrating 2D helical double layer, which is further extended via the interlayer π···π interactions into a 3D supramolecular structure. Complex 5 displays a pillared-layer 3D porous network with a (62.8)2(62.82.102) topology. Compound 6 shows an unprecedented 3D host-framework consisting of Zn6 clusters and exhibits a novel 3D (5,5,5,6,9)-connected topological net with the Schläfli symbol of (410.65)(419.616.8)(46.64)(47.63)2. The topology of 7 is an unprecedented binodal (4,4)-connected 3D network with the Schläfli symbol of (62.84)(42.82)2. Complex 8 exhibits a 3D (66) structure with left- and right-handed helical chains arranged alternately. Complex 9 is a novel trinodal (4,4,5)-connected 3D framework with the Schläfli symbol of (64.82)(65.8)(68.82). To the best of our knowledge, the 3D frameworks with (5,5,5,6,9)-connected net for 6, binodal (4,4)-connected for 7, and trinodal (4,4,5)-connected for 9 have never been documented to date. Moreover, the luminescent properties of 4 and 6 have been investigated.

Two novel Mg-based metal–organic framework isomers with the formula [Mg2(HCO2)2(NH2-BDC)(DMF)2]n (NH2-BDC = 2-amino-1,4-benzenedicarboxylate) have been synthesized based on a 6-connected [24-MC-6] metallacrown secondary building unit (SBU), which display a two-dimensional (2D) 36 net (1) and three-dimensional primitive rhombohedral net (2) derived from a different extended orientation of SBU, respectively. The 2D framework of 1 exhibits relevant thermal stability, solvents stability, high CO2 adsorption, and strong luminescent properties.

A series of novel multidimensional transition metal–organic frameworks (MOFs), [Cu(Hbcpb)2]n (1), [Co(bcpb)]n (2), [Co(Hbcpb)2(1,4-bib)]n (3), {[M(bcpb)(1,4-bimb)]·xH2O}n (M = Co (4), Cu (5), Ni (6), x = 1 for 5, 2 for 4 and 6), [Co(bcpb)(4,4′-bibp)]n (7), {[Co(bcpb)(4,4′-bibp)]·2H2O}n (8), and [Ni2(bcpb)2(4,4′-bimbp)2]n (9), were synthesized under hydrothermal conditions in the presence of N-donor ancillary ligands [H2bcpb = 3,5-bis(3-carboxyphenyl)pyridine, 1,4-bib = 1,4-bis(1H-imidazol-4-yl)benzene, 1,4-bimb = 1,4-bis(imidazol-1-ylmethyl)benzene, 4,4′-bibp = 4,4′-bis(imidazol-1-yl)biphenyl, 4,4′-bimbp = 4,4′-bis(imidazol-1-ylmethyl)biphenyl]. Their structures have been determined by single-crystal X-ray diffraction analyses and further characterized by elemental analyses, IR spectra, powder X-ray diffraction (PXRD), and thermogravimetric (TG) analyses. By adjusting the reaction pH, the H2bcpb ligand is partially deprotonated to give the Hbcpb– form in 1 and 3, and completely deprotonated to afford the bcpb2– form in 2 and 4–9. Complex 1 exhibits a two-dimensional (2D) (3,6)-connected kgd topology with the Schläfli symbol of (43)2(46·66·83). The three-dimensional (3D) framework of 2 is defined as a (4,4)-connected pts topology with the Schläfli symbol of (42·84). Complex 3 displays a (4,6)-connected pcu topology with the Schläfli symbol of (412·63) built from 44 2D nets with the help of 1,4-bib. Complexes 4–6 are isomorphism and show a 3D (3,5)-connected mbm framework with the Point Schläfli symbol of (4·62)(4·66·83). The supramolecular isomers of 7 and 8, resulted from the different pH in the reaction, exhibit (3,5)-connected (42·67·8)(42·6) 3,5-L2 and (4,6)-connected (44·610·8)(44·62) fsc topology, respectively. Complex 9 can be regard as an unprecedented (3,5)-connected 3D 3,5-T1 frameworks with the point Schläfli symbol of (42·65·83)(42·6). The results revealed that the crystal architectures and the coordination modes of H2bcpb are attributed to the factors, including metal cations, pH, and the N-donor ancillary ligands.

•Two Cu(II) coordination polymers were synthesized with a new semi-rigid V-type dicarboxylate ligand with hydroxyl groups.•Complexes 1 and 2 display double- and single-zigzag chain structures, respectively.•The framework of 1 possesses one-dimensional rhombic channels.•Complexes 1 and 2 exhibit moderate thermal stabilities.Two intriguing one-dimensional coordination polymers, [Cu2(dhmdb)2(H2O)2]⋅6H2O (1) and Cu(dhmdb)(1,10-phen) (2), have been hydrothermally synthesized and structurally characterized through exploring a new semi-rigid V-type dicarboxylate ligand with hydroxyl groups, 4,4′-(dihydroxymethylene)dibenzoic acid (H2dhmdb). Complexes 1 and 2 display double- and single-zigzag chain structures, respectively, which further result in two-dimensional supramolecular networks by O–H⋯O hydrogen-bonds and π⋯π stacking interactions. The network of 1 possesses one-dimensional rhombic channels along c axis with the size of about 8 × 8 Å. The phase purity and thermal stability of 1 and 2 have also been investigated.

•A 3D metal–organic framework consists of metal-carboxylate chains.•The 3D framework has 1D rhombic channels.•The framework displays a 4-connected ABW–zeolite topology.•The framework exhibits high thermal stability at 315 °C.•The framework shows anti-ferromagnetic properties.A novel three-dimensional metal–organic framework, [Mn(pydc)(DMF)]n (1) (pydc = pyridine-3,4-dicarboxylate, DMF = N,N-dimethylformamide), has been hydrothermally synthesized and structurally characterized, which consists of one-dimension Mn(COO)2 chains and rhombic channels. The porous complex 1 displays a 4-connected ABW–zeolite topology with vertex symbols of 4.6.4.6.6.82, and exhibits high thermal stability (315 °C) and anti-ferromagnetic properties.

A flexible coordination polymer 1 with interdigitated structure has been synthesized from 4,4′-(hexafluoroisopropylidene)bis(benzoic acid) ligand and Cd2+ salt, whose 3D interdigitated framework displays novel 5-connected BN topology involving both covalent and strong hydrogen bonds. The luminescent properties of 1 are discussed.A flexible 3D interdigitated coordination framework was mutually assembled from 2D layer with strong hydrogen bonds, which gives novel 5-connected BN topology.Research Highlights► The coordination polymer displays interdigitated structure. ► The 3D framework exhibits 5-connected BN topology involving both covalent and hydrogen bonds. ► The luminescent and thermol properties of compound are investigated.

Two novel Co(II)-organic frameworks with helical structures, [Co(hfipbb)(py)]n (1) and {[Co4(OH)(H2O)(hfipbb)3(Hhfipbb)(bpp)2]·H2O}n (2) (H2hfipbb = 4,4′-(hexafluoroisopropylidene)bis(benzoic acid), py = pyridine, bpp = 1,3-bis(4-pyridyl)propane), have been assembled from flexible bent ligands. Complex 1 displays a 2-fold parallel interpenetrated layer network with one-dimensional double helical channels, while 2 exhibits a three-dimensional pillared helical-layer open framework with six-connected self-penetrating topology based on a mixed dinuclear paddle-wheel cluster and tetranuclear [Co4(μ3-OH)2(μ2-OH2)2] steplike cluster.

A novel three-dimensional metal-organic framework, [Mn2(hfipbb)2(bpy)]n (1) (H2hfipbb = 4,4′-(hexafluoroisopropylidene)bis(benzoic acid), bpy = 4,4′-bipyridine), has been hydrothermally synthesized and structurally characterized. The complex consists of metal carboxylate chains, which are cross-linked to six adjacent chains through organic moieties forming extended three-dimensional networks. Complex 1 exhibits high thermal stability (450 °C) and antiferromagnetic properties.

A linear trimetallic cluster {[Cd3(bhnq)3(H2O)2](DMF)(H2O)3}n (1) has been synthesized from Cd(II) salts and a flexible hingelike ligand, 2,2′-bis(3-hydroxy-1,4-naphthoquinone). Sequential assembly of the linear trimetallic cluster as a new controlled second building unit with rigid covalent linker resulted in a one-dimensional hybrid cluster-based coordination polymer, {[Cd3(bhnq)3(4,4′-bipy)](DMF)(H2O)3}n 2, which is further assembled into a three-dimensional supramolecular framework with cavities via self-complementary π−π interactions.

Two supramolecular isomers with two-dimensional 44 rhombic-grid and three-dimensional 64·82 compressed-NbO frameworks, α-[Cd(SH)2(S-bztpy)]·2H2O (1) and β-[Cd(SH)2(E-bztpy)]·2H2O (2) (bztpy = 1,2,4,5-tetra(4-pyridyl)benzene), have been synthesized in a one-pot reaction, involving solvothermal in situ ligand generation and conformational isomers separation of the bztpy ligand. The variation in structural topology results from the conformational freedom of the bztpy ligand through rotation of the C—C bonds between pyridine and benzene rings, which imparts them with intriguingly different luminescence properties.

A 1D flexible zigzag coordination polymer, {[Zn(bac)2(bpp)] · 1.5H2O}n (1) (bac = 1-benzoylacetone, bpp = 1,3-bis(4-pyridyl)propane), has been synthesized by ambient evaporation of mixed solution and structurally characterized by single crystal X-ray diffraction. The zigzag chains in two different directions are entangled to generate a 2D interwoven network, which is stabilized by hydrogen bonding interactions. The powder X-ray diffraction (XRD) and thermogravimetric analysis (TGA) of 1 have also been studied.A 1D flexible zigzag coordination polymer, {[Zn(bac)2(bpp)] · 1.5H2O}n (1) (bac = 1-benzoylacetone, bpp = 1,3-bis(4-pyridyl)propane), has been synthesized and structurally characterized. The zigzag chains in two different directions are entangled to generate a 2D interwoven network, which is stabilized by hydrogen bonding interactions.

A novel 2D cobalt(II)-organic framework, [Co2(μ2-H2O)(hfipbb)2(py)3] · 2(py)]n (1) (H2hfipbb = 4,4′-(hexafluoroisopropylidene)bis(benzoic acid), py = pyridine), has been synthesized under hydrothermal reaction. Single-crystal X-ray diffraction revealed that 1 is a noninterpenetration (4,4) network based on unique tetranuclear clusters and double stranded organic linkers. The powder X-ray diffraction and thermogravimetric analysis of 1 have also been investigated.A novel 2D cobalt(II)-organic framework, [Co2(μ2-H2O)(hfipbb)2(py)3] · 2(py)]n (1) (H2hfipbb = 4,4′-(hexafluoroisopropylidene)bis(benzoic acid), py = pyridine), has been synthesized under hydrothermal reaction. Single-crystal X-ray diffraction revealed that 1 is a noninterpenetration (4,4) network based on unique tetranuclear clusters and double stranded organic linkers.

A hexagonal nanosheet LDH@ZIF-8 composite was fabricated by in situ growth of ZIF-8 on Zn–Al LDH without adding any zinc precursor, and exhibited a CO2 adsorption capacity of 1.0 mmol g−1 at room temperature and 1 bar, which was significantly higher than that of pure Zn–Al LDH or ZIF-8, indicating a synergy between ZIF-8 and Zn–Al LDH.

Metal–organic frameworks (MOFs) are considered as suitable materials for various applications in the area of photocatalysis. On the other hand, 2D BiOBr materials are efficient for the photodegradation of organic dyes under visible light illumination. In this work, BiOBr/NH2-MIL-125(Ti) composite photocatalysts with different NH2-MIL-125(Ti) content were prepared by incorporating NH2-MIL-125(Ti) with BiOBr using a co-precipitation method. A series of characterizations confirmed the strong synergistic effect between BiOBr and NH2-MIL-125(Ti). In rhodamine B (RhB) degradation experiments, the composite photocatalyst with a mass percent of 7 wt% NH2-MIL-125(Ti) exhibited an improved photocatalytic activity compared to pristine BiOBr and NH2-MIL-125(Ti). Furthermore, the enhanced photocatalytic performance under visible light illumination could be attributed to the Ti3+–Ti4+ intervalence electron transfer and synergistic effect between NH2-MIL-125(Ti) and BiOBr, and also resulted in a separation efficiency of photo-generated electron–hole pairs during the photocatalytic reaction. This study can open up numerous opportunities for the development of various MOF-based visible light photocatalysts when combined with 2D bismuth oxyhalide materials for applications in environmental cleaning.

A hierarchical NiO/NiMn-LDH nanosheet array on Ni foam was prepared via a facile two-step approach and exhibited a high specific capacitance (937 F g−1 at 0.5 A g−1) and good cycling stability (91% retention after 1000 cycles at 5 A g−1). The improved electrochemical performance is benefited from the synergistic properties of hierarchical NiO/LDH nanosheet composites on a conductive substrate.

Nanorods-composed yolk–shell bimetallic-organic frameworks microspheres are successfully synthesized by a one-step solvothermal method in the absence of any template or surfactant. Furthermore, hierarchical double-shelled NiO/ZnO hollow spheres are obtained by calcination of the bimetallic organic frameworks in air. The NiO/ZnO hollow spheres, as supercapacitor electrodes, exhibit high capacitance of 497 F g−1 at the current density of 1.3 A g−1 and present a superior cycling stability. The superior electrochemical performance is believed to come from the unique double-shelled NiO/ZnO hollow structures, which offer free space to accommodate the volume change during the ion insertion and desertion processes, as well as provide rich electroactive sites for the electrochemical reactions.