Coordination Polymer Derived Porous Carbon Activated in Situ by the ZnCl2 Dot: Capacitances Greatly Enhanced by Redox-Activity Additives in Electrolytes.

Herein, a 1D zinc coordination polymer [Zn(bibp)Cl2]∞ (CP-2-ZX) was assembled from the reaction of 4,4'-bis(imidazol-1-yl)-biphenyl (bibp) with ZnCl2. Through a calcination-thermolysis strategy, sponge-like highly porous carbon AC-Zn-CP was prepared by employing the coralloid sample of CP-2-ZX as the precursor. For comparisons, a series of activated carbon (AC-n) was obtained by the similar heating process on the mixture of bibp with ZnCl2 at different mass ratios. The results illustrate that the atomically dispersed ZnCl2 dot in the 1D chain of CP-2-ZX has an in situ activation effect on the generation of AC-Zn-CP, which can greatly promote the porosity and achieve high-efficiency utilization of ZnCl2. Therefore, the atomically dispersed activating agent provides a new method for environmentally friendly production of porous carbon materials. Significantly, the AC-Zn-CP electrode displays specific capacitance of 215 F g-1 in 3 M KOH solution, which will be largely promoted to 1419 F g-1 in the redox active electrolyte of K3[Fe(CN)6]/KOH. AC-Zn-CP also shows remarkable cycling stability (the capacity retention is 89.0% after 5000 cycles). Moreover, the fabricated symmetric supercapacitor owns a high energy density of 34.8 Wh kg-1 at 785.5 W kg-1. So, the AC-Zn-CP∩K3[Fe(CN)6] system has wide application prospects in supercapacitors.

Temperature-Dependent Morphologies of Precursors: Metal-Organic Framework-Derived Porous Carbon for High-Performance Electrochemical Double-Layer Capacitors.

In this work, three Cu metal-organic framework samples with tunable rhombic, squama, and trucated bipyramid morphologies have been synthesized at 0, 25, and 60 °C, respectively, and further employed as precursors to initially prepare Cu@C composites by the calcination-thermolysis procedure. Then Cu@C composites have been etched with HCl and subsequently activated with KOH to obtain activated porous carbon (APC-0, -25, and -60). Interestingly, APC-25 presents a loose multilevel morphology of cabbage and possesses the largest specific surface area (1880.4 m2 g-1) and pore volume (0.81 cm3 g-1) among these APC materials. Consequently, APC-25 also exhibits the highest specific capacitance of 196 F g-1 at 0.5 A g-1, and the corresponding symmetric supercapacitor cell (SSC) achieves a remarkable energy density of 11.8 Wh kg-1 at a power density of 350 W kg-1. Furthermore, APC-25 shows excellent cycling stability, and the loss of capacitance is only 7.7% even after 10000 cycles at 1 A g-1. Significantly, five light-emitting diodes can be lit by six SSCs, which proves that APC-25 can be used in energy storage devices.

Controllable Syntheses of MOF-Derived Materials.

Metal-organic frameworks (MOFs), as an important kind of porous inorganic-organic hybrid materials with inherent outstanding physicochemistry characteristics, can be widely applied as versatile precursors for the facile preparation of functional MOF-derived materials. However, there are plenty of sophisticated factors during the synthetic process, which is far from reaching the goal of effectively controlling the nature of MOF-derived materials (such as the composition, morphology and surface area). Therefore, it is urgently necessary to develop regular protocols and concepts for controllable syntheses of MOF-derived materials. In this minireview, we mainly summarize and analyze complicated factors in the fabrication of MOF-derived materials according to recently reported literatures, and this provides a new insight into the rational design and syntheses of MOF-derived materials.

Six Isomorphous Window-Beam MOFs: Explore the Effects of Metal Ions on MOF-Derived Carbon for Supercapacitors.

Six isomorphous metal-organic frameworks (MOFs) with a 3D window-beam architecture have been synthesized from solvothermal reactions, and are named Zn, Cd, Ni, Co, Mn and Cu-MOF, respectively. The series of MOFs was utilized as precursors to synthesize MOF-derived carbon with different morphologies. Zn and Cd-MOFs lead to the derivation of porous carbons (PCs), which exhibit remarkable BET specific surface areas. For derivates of Ni, Co and Mn-MOFs, graphitized carbons (GCs) show some carbon graphitization, but their BET specific surface areas are relatively small. C-Cu has the smallest BET specific surface area, and there is no carbon graphitization. Therefore, the metal ion of the parent MOF exerts a crucial effect on the preparation of MOF-derived carbon, such as the pore-forming effect of Zn and Cd species, and catalytic graphitization of Ni, Co, and Mn species. The capacitances of MOF-derived carbon follow the sequence of PCs>GCs>C-Cu, which reveals that the specific surface area plays a dominant role in the capacitive performance of electrical double layer capacitors (EDLCs), and that the graphitization could improve the capacitance. Significantly, PC-Zn exhibits the best specific capacitance (138 F g-1 at 0.5 Ag-1 ), and excellent life cycle, which can be applied as an electrode material in supercapacitors.

Solvent-Induced Cadmium(II) Metal-Organic Frameworks with Adjustable Guest-Evacuated Porosity: Application in the Controllable Assembly of MOF-Derived Porous Carbon Materials for Supercapacitors.

In this work, five new cadmium metal-organic frameworks (Cd-MOFs 1-5) have been synthesized from solvothermal reactions of Cd(NO3 )2 ⋅4 H2 O with isophthalic acid and 1,4-bis(imidazol-1-yl)-benzene under different solvent systems of CH3 OH, C2 H5 OH, (CH3 )2 CHOH, DMF, and N-methyl-2-pyrrolidone (NMP), respectively. Cd-MOF 1 shows a 3D diamondoid framework with 1D rhombic and hexagonal channels, and the porosity is 12.9 %. Cd-MOF 2 exhibits a 2D (4,4) layer with a 1D parallelogram channel and porosity of 23.6 %. Cd-MOF 3 has an 8-connected dense network with the Schäfli symbol of [424 ⋅64 ] based on the Cd6 cluster. Cd-MOFs 4-5 are isomorphous, and display an absolutely double-bridging 2D (4,4) layer with 1D tetragonal channels and porosities of 29.2 and 28.2 %, which are occupied by DMF and NMP molecules, respectively. Followed by the calcination-thermolysis procedure, Cd-MOFs 1-5 are employed as precursors to prepare MOF-derived porous carbon materials (labeled as PC-me, PC-eth, PC-ipr, PC-dmf and PC-nmp), which have the BET specific surface area of 23, 51, 10, 122, and 96 m2 g-1 , respectively. The results demonstrate that the specific surface area of PCs is tuned by the porosity of Cd-MOFs, where the later is highly dependent on the solvent. Thereby, the specific surface area of PCs could be adjusted by the solvent used in the synthese of MOF precusors. Significantly, PCs have been further activated by KOH to obtain activated carbon materials (APCs), which possess even higher specific surface area and larger porosity. After a series of characterization and electrochemical investigations, the APC-dmf electrode exhibits the best porous properties and largest specific capacitances (153 F g-1 at 5 mV s-1 and 156 F g-1 at 0.5 Ag-1 ). Meanwhile, the APC-dmf electrode shows excellent cycling stability (ca. 84.2 % after 5000 cycles at 1 Ag-1 ), which can be applied as a suitable electrode material for supercapacitors.

Benzoate Acid-Dependent Lattice Dimension of Co-MOFs and MOF-Derived CoS2@CNTs with Tunable Pore Diameters for Supercapacitors.

Herein three novel cobalt metal-organic frameworks (Co-MOFs) with similar ingredients, [Co(bib)(o-bdc)]∞ (1), [Co2(bib)2(m-bdc)2]∞ (2), and {[Co(bib)(p-bdc)(H2O)](H2O)0.5}∞ (3), have been synthesized from the reaction of cobalt nitrate with 1,4-bis(imidazol-1-yl)benzene (bib) and structure-related aromatic acids (1,2-benzenedicarboxylic acid = o-bdc, 1,3-benzenedicarboxylic acid = m-bdc, and 1,4-benzenedicarboxylic acid = p-bdc) by the solvothermal method. It is aimed to perform systematic research on the relationship among the conformation of benzoate acid, lattice dimension of Co-MOF, and pore diameter of MOF-derived carbon composite. Through the precursor strategy, Co-MOFs 1-3 have been utilized to synthesize porous cobalt@carbon nanotube composites (Co@CNTs). After the in situ gas-sulfurization, secondary composites CoS2@CNTs were successfully obtained, which kept similar morphologies of corresponding Co@CNTs without destroying previous highly dispersed structures. Co-MOFs and two series of composites (Co@CNTs and CoS2@CNTs) have been well characterized. Topology and Brunauer-Emmett-Teller analyses elucidate that the bdc2- ion could control the pore diameters of MOF-derived carbon composites by adjusting the lattice dimension of Co-MOFs. The systematic studies on electrochemical properties demonstrate that (p)-CoS2@CNT possesses hierarchical morphology, moderate specific surface area, proper pore diameter distribution, and high graphitization, which lead to remarkable specific capacitances (839 F g-1 at 5 mV s-1 and 825 F g-1 at 0.5 A g-1) in 2 M potassium hydroxide solution. In addition, the (p)-CoS2@CNT electrode exhibits good electrochemical stability and still retains 82.9% of initial specific capacitance at the current density of 1 A g-1 after 5000 cycles.

Controlling the BET Surface Area of Porous Carbon by Using the Cd/C Ratio of a Cd-MOF Precursor and Enhancing the Capacitance by Activation with KOH.

Herein, four new cadmium metal-organic frameworks (Cd-MOFs), [Cd(bib)(bdc)]∞ (1), [Cd(bbib)(bdc)(H2 O)]∞ (2), [Cd(bibp)(bdc)]∞ (3), and [Cd2 (bbibp)2 (bdc)2 (H2 O)]∞ (4), have been constructed from the reaction of Cd(NO3 )2 ⋅4 H2 O with 1,4-benzenedicarboxylate (H2 bdc) and structure-related bis(imidazole) ligands (1,4-bis(imidazol-1-yl)benzene (bib), 1,4-bis(benzoimidazol-1-yl)benzene (bbib), 4,4'-bis(imidazol-1-yl)biphenyl (bibp), and 4,4'-bis(benzoimidazol-1-yl)biphenyl (bbibp)) under solvothermal conditions. Cd-MOF 1 shows a 2D (4,4) lattice with parallel interpenetration, whereas 2 displays an interesting 3D interpenetrating dia network, 3 exhibits an unusual 3D interpenetrating dmp network, and 4 presents a 3D self-catenated pillar-layered framework with a Schäfli symbol of [43 ⋅63 ]2 ⋅[46 ⋅616 ⋅86 ]. The structural diversity indicates that the backbone of the bis(imidazole) ligand (including the terminal group and spacer) plays a crucial role in the assembly of mixed-ligand frameworks. By using the pore-forming effect of cadmium vapor, for the first time we have utilized these Cd-MOFs as precursors to further prepare porous carbon materials (PCs) in a calcination-thermolysis procedure. These PCs show different porous features that correspond to the topological structures of Cd-MOFs. Significantly, it was found that the specific surface area and capacitance of PCs are tuned by the Cd/C ratio of the MOF. Furthermore, the as-synthesized PCs were processed with KOH to obtain activated porous carbon materials (APCs) with higher specific surface area and porosity, which greatly promoted the energy-storage capacity. After full characterization, we found that APC-bib displays the largest specific surface area (1290 m2 g-1 ) and total pore volume (1.37 cm3 g-1 ) of this series of carbon materials. Consequently, APC-bib demonstrates the highest specific capacitance of 164 F g-1 at a current density of 0.5 A g-1 , and also excellent retention of capacitance (≈89.4 % after 5000 cycles at 1 A g-1 ). Therefore, APC-bib has great potential as the electrode material in a supercapacitor.

Hierarchically Flower-like N-Doped Porous Carbon Materials Derived from an Explosive 3-Fold Interpenetrating Diamondoid Copper Metal-Organic Framework for a Supercapacitor.

A peculiar copper metal-organic framework (Cu-MOF) was synthesized by a self-assembly method, which presents a 3-fold interpenetrating diamondoid net based on the square-planar Cu(II) node. Although it exhibits a high degree of interpenetration, the Cu-MOF still exhibits a one-dimensional channel, which provides a template for constructing porous materials through the "precursor" strategy. Furthermore, the explosive ClO4(-) ion, which resided in the channel, could induce the quick decomposition of organic ingredients and release a huge amount of gas, which is beneficial for the porosity of postsynthetic materials. Significantly, we first utilize this explosive MOF to prepare a series of Cu@C composites through the calcination-thermolysis method at different temperatures, which contain copper particles exhibiting various shapes and combinations with the carbon substrate. Considering the hole-forming effect of copper particles, Cu@C composites were etched by HCl to afford a sequence of hierarchically flower-like N-doped porous carbon materials (NPCs), which retain the original morphology of the Cu-MOF. Interestingly, NPC-900, originating from the calcination of the Cu-MOF at 900 °C, exhibits a more regular flower-like morphology, the largest specific surface area, abundant porosities, and multiple nitrogen functionalities. The remarkable specific capacitances are 138 F g(-1) at 5 mV s(-1) and 149 F g(-1) at 0.5 A g(-1) for the NPC-900 electrode in a 6 M potassium hydroxide aqueous solution. Moreover, the retention of capacitance remains 86.8% (125 F g(-1)) at 1 A g(-1) over 2000 cycles, which displays good chemical stability. These findings suggest that NPC-900 can be applied as a suitable electrode for a supercapacitor.

An atom-economy route for the fabrication of α-MnS@C microball with ultrahigh supercapacitance: The significance of in-situ vulcanization.

In this study, we have introduced a facile, effective and low-cost process of in-situ vulcanization for preparing α-MnS@C composite via simple calcination-thermolysis of one manganese coordination polymer (CP-1-ZX). In this procedure, the 1D chain [-Mn-SO4-]∞ in CP-1-ZX is completely reduced into α-MnS by the as-synthesized carbon. So the in-situ vulcanization provides an atom-economy route to fabricate sulfides by using least synthetic steps and sulfur sources. The α-MnS@C composite maintains the microball morphology of CP-1-ZX precursor, which is composed of many core-shell nanoparticles. Due to high porosity, hierarchical pores and good conductivity, the specific capacitance of α-MnS@C is up to 856F g-1 at 0.5 A g-1, and keeps 82% retention after 5000 cycles. Meanwhile, one asymmetric supercapacitor cell (ASC) is assembled by combining α-MnS@C with commercial active carbon (AC). The α-MnS@C//AC device delivers prominent energy density of 28.4 Wh kg-1 at power density of 395 W kg-1, and still retains 17.8 Wh kg-1 at 8020 W kg-1. Furthmore, four tandem ASC devices can brightly glow a lamp bulb for 30 s. Therefore, the α-MnS@C composite shows great applications in supercapacitors.

New 3D coordination polymers constructed from pillared metal-formate Kagomé layers exhibiting spin canting only in the nickel(II) complex.

Sparked by the strategy of pillared-layer MOFs, three formate coordination polymers, {[Ni(2)(HCO(2))(3)(L)(2)](NO(3)).2H(2)O}(infinity) (1), {[Co(2)(HCO(2))(3)(L)(2)](HCO(2)).2H(2)O}(infinity) (2), and {[Cu(2)(HCO(2))(3)(L)(2)](HCO(2)).2H(2)O}(infinity) (3), have been synthesized by employing the rodlike ligand 4,4'-bis(imidazol-1-yl)biphenyl (L) as the pillar. Structural analysis indicates that the title complexes 1-3 are isostructural compounds, which possess metal-formate 2D layers perpendicularly pillared by the ligand L to afford a 3D open framework. This is an interesting example of a Kagome lattice based on the formate mediator. Moreover, the formate anion of this 2D Kagome layer exhibits various bridging modes: anti-anti, syn-anti, and 3.21 modes. Their magnetic measurements reveals that only complex 1 presents the spin canting phenomenon, while its isostructural Co(II) and Cu(II) complexes are simply paramagnets with antiferromagnetic coupling.

Di-µ-chlorido-chlorido-1κCl-(µ-1-phenyl-3-phenyl-imino-but-1-enolato-1:2κO:O,N)bis-(1-phenyl-3-phenyl-imino-but-1-enolato)-1κN,O;2κN,O-dichromium(III) toluene disolvate.

In the title dichromium complex, [Cr(2)(C(16)H(14)NO)(3)Cl(3)]·2C(7)H(8), each Cr(III) atom has a distorted octa-hedral coordination geometry. The complex mol-ecule has three six-membered chelate rings formed by hydroxy-butane-imine ligands and the two Cr(III) atoms are bridged by two Cl atoms and one O atom.

4,4'-Bis(benzimidazol-1-yl)biphen-yl.

The mol-ecule of the title compound, C(26)H(18)N(4), resides on a crystallographic inversion centre with a dihedral angle of 44.94 (5)° between the benzimidazole ring system and the benzene ring. The primary hydrogen bond is C-H⋯N and inversion-related pairs of these generate a chain of rings along the c-axis direction; π⋯π stacking involving the benzimidazole groups with inter-planar separations of ca 3.4 Šcomplete the inter-actions.

Tuning zinc(II) coordination architectures by rigid long bis(triazole) and different carboxylates: Synthesis, structures and fluorescence properties.

Three metal-organic coordination polymers containing rigid bis(triazole) ligand, namely, [Zn1.5(btb)(nbta)(H2O)]n (1), {[Zn(btb)(3-nph)]·(H2O)}n (2) and [Zn(btb)(4-nph)]n (3) (btb=4,4'-bis(1,2,4-triazolyl-1-yl)-biphenyl, 3-H2nph=3-nitrophthalic acid, H3nbta=5-nitro-1,2,3-benzenetricarboxylic acid, and 4-H2nph=4-nitrophthalic acid) were synthesized under hydrothermal conditions and structurally characterized by X-ray single-crystal diffraction. Complex 1 possesses an interesting 3D coordination framework with a rarely binodal (4,4)-connected frl topological structure. Complexes 2 and 3 exhibit similiar 2D (4,4) grid layers with different point symbol (4(4)·6(4)) in 2 and (4(4)·6(2)) in 3. Furthermore, thermal stability of these compounds has been discussed. Complexes 1-3 exhibit strong solid-state fluorescence at room temperature in solid state.

1D-3D mixed-ligand frameworks with an unusual dmp topology tuned by intersection angles of isomeric benzenedicarboxylates: magnetic properties, gas-dependent calcination-thermolysis and energy storage performances.

In this work, three isomeric benzenedicarboxylates, 1,2-benzenedicarboxylic acid (o-H2bdc), 1,3-benzenedicarboxylic acid (m-H2bdc), and 1,4-benzenedicarboxylic acid (p-H2bdc) have been utilized as the ancillary ligands to perform a systematic study on the structural diversity of mixed-ligand frameworks. The solvothermal reactions of Co(NO3)2 with these aromatic acids and the primary ligand 4,4'-bis(imidazolyl)biphenyl (bibp) afford three novel coordination polymers, {[Co6(bibp)3(o-bdc)6(H2O)](CH3CN)1.5}∞ (1), [Co(bibp)(m-bdc)]∞ (2), and [Co(bibp)(p-bdc)]∞ (3). Owing to the different orientations of the carboxylate groups, the benzenedicarboxylates adopt various bridging modes to connect the Co(II) ions into a series of 1D carboxylate∩cobalt architectures based on the 1D chain, binuclear and single-ion magnetic units, respectively. These 1D architectures are further decorated by the bibp ligand to afford a 1D belt for , 2D double-bridging (4,4) sheet for 2, and an unusual 3D dmp framework for 3. Significantly in 3, three equivalent frameworks are interlocked with each other to represent an unprecedented three-fold interpenetrating dmp network. The structural diversity indicates that the benzenedicarboxylate plays an essential role in the assembly of mixed-ligand frameworks, and the orientation of the carboxylate group exerts an important influence on the nucleation, dimensionality and also interpenetration. Furthermore, the magnetic properties of 1 and 2 have been studied by fitting the experimental data as possible, and the magneto-structural correlation of 2 has also been well discussed. Importantly, CoO and Co3O4 were obtained from the controllable thermolysis of crystals of 1 via simple calcination treatment under different gas environments. The as-synthesized cobalt oxides display good crystallinity and appear as micro- or nanoparticles, which can be applied as supercapacitor electrodes as demonstrated by their energy storage performance in 2 M KOH electrolyte.

An unprecedented double-bridging interpenetrating α-Po network based on a new heterometallic cluster {Cu4Mo6}.

A new coordination polymer of polyoxomolybdate, {[Cu(4)(bbp)(5)Mo(6)O(22)]·(H(2)O)(4)}(∞) (bbp = 1,4-bis(benzoimidazol-1-yl)phenyl), has been synthesized under solvothermal reaction, which represents a double-bridging interpenetrating α-Po network based on the bimetallic cluster {Cu(4)Mo(6)}. The thermogravimetric and electrochemical behaviors have also been studied.

Homospin single-chain magnet with 1D ferromagnetic azido-cobalt Ising-type chain.

A new 2D coordination polymer with an azide-bridged 1D homospin chain is synthesized, which shows slow magnetic relaxation and step hysteresis loop, and is ascribed to be a typical Ising-type single-chain magnet.