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1.
Embedding cubane [M4(OH)4] (M=Ni, Co) clusters within the matrix of metal–organic frameworks (MOFs) is a strategy to develop materials with unprecedented synergistic properties. Herein, a new material type based on the pore‐space partition of the cubic primitive minimal‐surface net (MOF‐14‐type) has been realized. CTGU‐15 made from the [Ni4(OH)4] cluster not only has very high BET surface area (3537 m2 g?1), but also exhibits bi‐microporous features with well‐defined micropores at 0.86 nm and 1.51 nm. Furthermore, CTGU‐15 is stable even under high pH (0.1 m KOH), making it well suited for methanol oxidation in basic medium. The optimal hybrid catalyst KB&CTGU‐15 (1:2) made from ketjen black (KB) and CTGU‐15 exhibits an outstanding performance with a high mass specific peak current of 527 mA mg?1 and excellent peak current density (29.8 mA cm?2) at low potential (0.6 V). The isostructural cobalt structure (CTGU‐16) has also been synthesized, further expanding the application potential of this material type.  相似文献   

2.
The title bimetallic compound, [Yb43‐OH)4(C6H13NO2)7(H2O)7][ZnCl4][ZnCl3(OH)]Cl4·8H2O, was synthesized at near physiological pH (6.0). The compound exhibits some novel structural features, including an asymmetric [Yb43‐OH)4(l ‐leucine)7(H2O)7]8+ complex cation in which four OH groups act as bridging ligands, linking four Yb3+ cations into a Yb4O4 structural unit. Each pair of adjacent Yb3+ ions is further bridged by one carboxy group from a leucine ligand. Water mol­ecules and a monodentate leucine ligand also coordinate to Yb3+ ions, completing their eight‐coordinate square‐antiprismatic coordination. The Yb43‐OH)4(l ‐leu­cine)7(H2O)7]8+ cation, the [ZnCl4]2−, [ZnCl3OH]2− and Cl anions, and the lattice water mol­ecules are linked via hydrogen bonds.  相似文献   

3.
The MnII‐based porous metal‐organic framework, [Mn3(btca)2(HCOO)(μ3‐OH)(H2O)2] · 2DMF ( 1 ) (H2btca = benzotriazole‐5‐carboxylate acid), was prepared by the solvothermal reaction of Mn(CH3COO)2 · 4H2O and H2btca, which was characterized by infrared spectroscopy, thermogravimetric analyses, and X‐ray crystallographic study. 1 exhibits 3D framework with 1D rectangle channels constructed by the strip‐shaped chains containing [Mn53‐OH)2(btca)4] pentaclusters subunits. Furthermore, the magnetic measures show that 1 exhibits weak ferromagnetic behavior at low temperature.  相似文献   

4.
张曙光  冯云龙 《中国化学》2009,27(5):877-881
四唑酸(–CN4H)与羧酸(–COOH)具有相似的酸性。对苯酚四唑硫酮(H2L)可以作为单齿(–S或–N)或双齿(–N, N或–N, S)配体与金属离子配位形成配位化合物。合成了4个以H2L为配体的金属(II)配合物:Co(HL)2(Py)2(H2O)2 (1), [Mn(HL)2(H2O)4]·2H2O (2), Mn(HL)2(Phen)2 (3), and [Zn(HL)2(Phen)2]·0.5H2O·1.5CH3OH (4),并用X−射线单晶衍射法测定了晶体结构。晶体结构分析表明,在这些配合物中所有的中心金属原子均呈现六配位的八面体构型。在配合物1和2中,HL–配体以氧原子与中心金属原子配位,而在配合物3和4中HL–配体则以硫原子与中心金属原子配位。  相似文献   

5.
A large cationic triangular metallo‐prism, [Ru6(p‐PriC6H4Me)6(tpt)2(dhbq)3]6+ ( 1 )6+, incorporating p‐cymene ruthenium building blocks, bridged by 2,5‐dihydroxy‐1,4‐benzoquinonato (dhbq) ligands, and connected by two 2,4,6‐tri(pyridin‐4‐yl)‐1,3,5‐triazine (tpt) subunits, allows the permanent encapsulation of the triphenylene derivatives hexahydroxytriphenylene, C18H6(OH)6 and hexamethoxytriphenylene, C18H6(OMe)6. These two cationic carceplex systems [C18H6(OH)6⊂ 1 ]6+ and [C18H6(OMe)6⊂ 1 ]6+ have been isolated as their triflate salts. The molecular structure of these systems has been established by one‐dimensional 1H ROESY NMR experiments as well as by the single‐crystal structure analysis of [C18H6(OMe)6⊂ 1 ][O3SCF3]6.  相似文献   

6.
A novel antimony substituted polyoxomolybdate has been synthesized and characterized by X‐ray structure analysis, energy dispersive X‐ray fluorescence analysis, Raman and IR spectroscopy. The [Sb4Mo12(OH)6O48]10‐ anion exhibits a central Sb4(OH)6O14 core where all SbV atoms are coordinated octahedrally by six oxygen atoms. It represents a novel type of heteropolyanion with no known analogous structure in literature.  相似文献   

7.
A porous Na3V2(PO4)3 cathode material coated uniformly with a layer of approximately 6 nm carbon has been synthesized by the sol–gel method combined with a freeze‐drying process. The special porous morphology and structure significantly increases the specific surface area of the material, which greatly enlarges the contact area between the electrode and electrolyte, and consequently supplies more active sites for sodium ions. When employed as a cathode material of sodium‐ion batteries, this porous Na3V2(PO4)3/C exhibits excellent rate performance and cycling stability; for instance, it shows quite a flat potential plateau at 3.4 V in the potential window of 2.7–4.0 V versus Na+/Na and delivers an initial capacity as high as 118.9 and 98.0 mA h g?1 at current rates of 0.05 and 0.5 C, respectively, and after 50 cycles, a good capacity retention of 92.7 and 93.6 % are maintained. Moreover, even when the discharge current density is increased to 5 C (590 mA g?1), an initial capacity of 97.6 mA h g?1 can still be achieved, and an exciting capacity retention of 88.6 % is obtained after 100 cycles. The good cycle performance, excellent rate capability, and moreover, the low cost of Na3V2(PO4)3/C suggest that this material is a promising cathode for large‐scale sodium‐ion rechargeable batteries.  相似文献   

8.
郭倩玲  马淑兰  朱文祥  刘迎春  张静 《中国化学》2005,23(10):1387-1390
The X-ray crystallographic structure was reported for a dinuclear copper(Ⅱ) complex with a tetraanionic ligand of p-tert-butylsulfonylcalix[4]arene [Cu2L(CH3OH)6]·4CH3OH (H4L=p-tert-butylsuffonylcalix[4]arene). The complex belongs to triclinic system, P1^-- space group, with a = 1.2303(3) nm, b = 1.2377(3) nm, c = 1.3110(3) nm, a =66.862(4)°, β= 67.206(4)°, γ=61.711(3)°, Z= 1, V= 1.5659(7) nm^3, Dc= 1.371 g/cm^3, F(000) = 682,μ(Mo Kα) = 0.883 mm^-1, R1 =0.0325, wR2=0.0870. In this complex, the calix[4]arene acts as a bis-tridentate chelating ligand with the 1,2-alternate conformation.  相似文献   

9.
Two kinds of inorganic gadolinium(III)‐hydroxy “ladders”, [2×n] and [3×n], were successfully trapped in succinate (suc) coordination polymers, [Gd2(OH)2(suc)2(H2O)]n ? 2n H2O ( 1 ) and [Gd6(OH)8(suc)5(H2O)2]n ? 4n H2O ( 2 ), respectively. Such coordination polymers could be regarded as alternating inorganic–organic hybrid materials with relatively high density. Magnetic and heat capacity studies reveal a large cryogenic magnetocaloric effect (MCE) in both compounds, namely (ΔH=70 kG) 42.8 J kg?1 K?1 for complex 1 and 48.0 J kg?1 K?1 for complex 2 . The effect of the high density is evident, which gives very large volumetric MCEs up to 120 and 144 mJ cm?3 K?1 for complexes 1 and 2 , respectively.  相似文献   

10.
The title compound, {[Zn4(C8H4O4)3(OH)2(C12H6N2O2)2]·2H2O}n, has been prepared hydrothermally by the reaction of Zn(NO3)2·6H2O with benzene‐1,4‐dicarboxylic acid (H2bdc) and 1,10‐phenanthroline‐5,6‐dione (pdon) in H2O. In the crystal structure, a tetranuclear Zn4(OH)2 fragment is located on a crystallographic inversion centre which relates two subunits, each containing a [ZnN2O4] octahedron and a [ZnO4] tetrahedron bridged by a μ3‐OH group. The pdon ligand chelates to zinc through its two N atoms to form part of the [ZnN2O4] octahedron. The two crystallographically independent bdc2− ligands are fully deprotonated and adopt μ3‐κOO′:κO′′ and μ4‐κOO′:κO′′:κO′′′ coordination modes, bridging three or four ZnII cations, respectively, from two Zn4(OH)2 units. The Zn4(OH)2 fragment connects six neighbouring tetranuclear units through four μ3‐bdc2− and two μ4‐bdc2− ligands, forming a three‐dimensional framework with uninodal 6‐connected α‐Po topology, in which the tetranuclear Zn4(OH)2 units are considered as 6‐connected nodes and the bdc2− ligands act as linkers. The uncoordinated water molecules are located on opposite sides of the Zn4(OH)2 unit and are connected to it through hydrogen‐bonding interactions involving hydroxide and carboxylate groups. The structure is further stabilized by extensive π–π interactions between the pdon and μ4‐bdc2− ligands.  相似文献   

11.
A pure inorganic 2D network molybdophosphate, [Mn3Mo12O24(OH)6(HPO3)8(H2O)6]4? ( 1 a ), synthesized through microwave irradiation with the existence of Mn2+ and organic cations and isolated as [(CH3)2NH2]3Na[Mn3Mo12O24(OH)6(HPO3)8(H2O)6] ? 12 H2O ( 1 ), is found to possess highly enhanced performance in lithium‐ion batteries’ anode materials. The molecule shows multielectron redox properties suitable for producing anode materials with a specific capacity of 602 mA h g?1 at 100 mA g?1 after 50 cycles in lithium‐ion batteries, although its specific capacity is the highest among all the reported pure inorganic 2D polyoxometalates to date, the cyclic stability is not that satisfactory. A hybrid nanocomposite of this 2D network and polypyrrole cations effectively reduces the capacity fading in initial cycles, and increases the stability and improves the electrochemical performance of lithium‐ion batteries as well.  相似文献   

12.
Germanophosphates, as a young class of metal phosphates, have been less reported but might possess more diverse structural types and potential applications. Here, two one‐dimensional (1D) alkali‐metal germanophosphates (GePOs), namely, hydrogen hexakis(μ‐hydrogen phosphato)digermaniumtrirubidium, HRb3Ge2(HPO4)6 ( 1 ), and caesium bis(μ‐hydrogen phosphato)(μ‐hydroxido)germanium, CsGe(HPO4)2(OH) ( 2 ), have been prepared by the solvothermal method. Compound 1 shows 1D [Ge(HPO4)6] chains along the c axis formed by GeO6 octahedra and PO4 tetrahedra, with Rb+ cations dissociated between the chains. Compound 2 also exhibits 1D [Ge(HPO4)4(OH)2] chains constructed from adjacent Ge(HPO4)4(OH)2 octahedra, with Cs+ cations dissociated between the chains. XRD, TGA, IR and UV–Vis–NIR absorption spectra are presented and discussed for both compounds.  相似文献   

13.
利用水热法合成了两种过渡金属配合物为模板剂的含水硼酸盐晶体Co(en)3[B4O5(OH)4]Cl·3H2O(1) 和 [Ni(en)3][B5O6(OH)4]2·2H2O (2),并通过元素分析、X射线单晶衍射、红外光谱及热重分析对其进行了表征。化合物1晶体结构的主要特点是在所有组成Co(en)33+, [B4O5(OH)4]2–, Cl– 和 H2O之间通过O–H…O、O–H…Cl、N–H…Cl和N–H…O四种氢键连接形成网状超分子结构。化合物2晶体结构的特点是[B5O6(OH)4]–阴离子通过O–H…O氢键连接形成沿a方向有较大通道的三维超分子骨架,模板剂[Ni(en)3]2+阳离子和结晶水分子填充在通道中。  相似文献   

14.
Two coordination compounds [Pb4(BDT)3(OH)2(H2O)4]·H2O ( 1 ) and [Mn(H2O)6]·(HBDT)2·2H2O ( 2 ) [H2BDT?5,5′‐(1,4‐phenylene)bis(1H‐tetrazole)] had been hydrothermally synthesized. 1 and 2 had been characterized by single‐crystal X‐ray diffraction, IR, elemental and thermal analyses. Structural analysis reveals that 1 exhibits 2D layer structure extended through BDT with two different coordination modes rings in transverse and vertical. 2 consists of [Mn(H2O)6]2+, free HBDT and water. In addition, 1 and 2 were explored as luminescent materials and additives to promote the thermal decomposition of ammonium perchlorate by differential scanning calorimetry.  相似文献   

15.
Several new donor–acceptor adducts of niobium and tantalum pentaazide with N‐donor ligands have been prepared from the pentafluorides by fluoride–azide exchange with Me3SiN3 in the presence of the corresponding donor ligand. With 2,2′‐bipyridine and 1,10‐phenanthroline, the self‐ionization products [MF4(2,2′‐bipy)2]+[M(N3)6]?, [M(N3)4(2,2′‐bipy)2]+[M(N3)6]? and [M(N3)4(1,10‐phen)2]+[M(N3)6]? were obtained. With the donor ligands 3,3′‐bipyridine and 4,4′‐bipyridine the neutral pentaazide adducts (M(N3)5)2?L (M=Nb, Ta; L=3,3′‐bipy, 4,4′‐bipy) were formed.  相似文献   

16.
A new cyano‐bridged binuclear 4f‐3d complex Sm(DMSO)4‐(H2O)3Cr(CN)6 was synthesized and characterized by single crystal structure analysis. It crystallizes in monoclinic, space group P21 with a=0.9367(2) nm, b = 1.3917(3) nm, c = 1.1212(2) run, β = 99.88(3)° and Z = 2. In this binuclear complex, Sm atom is eight coordinated and linked to the Cr atom by a cyano bridge. The molecules packs to form 3D structure due to the hydrogen bonds among them. [K3(18‐C‐6)3(H2O)4]Cr(CN)6·3H2O (18‐C‐6 represents 18‐crown‐6‐ether) that was synthesized as a byproduct in the preparation of a Gd—Cr complex is also structurally characterized. Crystal data: triclinic, space group P‐l with a = 1.0496(7) nm, b= 1.1567(14) nm, c = 1.3530(13) nm, a = 94.15(9)°, β = 96.04(8)°, γ = 95.25(9)° and Z = l. [K3(18‐C‐6)3(H2O)4]‐Cr(CN)6·3H2O consists of ionic [K3(18‐C‐6)3(H2O)4]3+ and [Cr(CN)6]3‐ pairs, of which the [K3(18‐C‐6)3(H2O)4]3+ ion is a trinuclear duster connected by water, and K atoms are eight coordinated by eight oxygen atoms of one 18‐C‐6 and two water molecules.  相似文献   

17.
The hydrothermal reaction of Cu(CH3COO)2·H2O, H3BO3, ethylenediamine and H2O in a molar ratio of 3:20:9:222 at 140°C for 5 d yields the deep blue crystals of a new copper polyborate [Cu(en)2B(OH)3]· [B5O5(OH)7] (en?H2NCH2CH2NH2) in 70% yield. It crystallizes in monoclinic system, space group P21/c, with unit cell dimensions, a=1.2779(2) nm, b=1.0167(15) nm, c=1.5019(2) nm, β=90.30(2)°, Z=4. The crystal structure of this compound consists of [Cu(en)2B(OH)3]2+ cation and [B5O5(OH)7]2? anion, which are linked together through hydrogen bonding interactions and electrostatic forces, forming an interesting three‐dimensional framework. The [B5O5(OH)7]2? anion is constituted of [B4O5(OH)4]2? anion and discrete B(OH)3 group which attaches to the side of [B4O5(OH)4]2? through intramolecular hydrogen bonds. Fundamental vibrational modes of this compound were identified and band assignments were made. The middle bands observed at 882 and 575 cm?1 in Raman spectrum are the characteristic peak of B(OH)3 group and [B4O5(OH)4]2? anion, respectively. Additionally the thermal behavior of title compound was recorded and its decomposition mechanism was discussed.  相似文献   

18.
The ionic conductivity properties of the face‐centered cubic [Ni8(OH)4(H2O)2(BDP_X)6] (H2BDP_X=1,4‐bis(pyrazol‐4‐yl)benzene‐4‐X with X=H ( 1 ), OH ( 2 ), NH2 ( 3 )) metal–organic framework (MOF) systems as well as their post‐synthetically modified materials K[Ni8(OH)5(EtO)(BDP_X)5.5] ( 1@KOH , 3@KOH ) and K3[Ni8(OH)3(EtO)(BDP_O)5] ( 2@KOH ), which contain missing‐linker defects, have been studied by variable temperature AC impedance spectroscopy. It should be noted that these modified materials exhibit up to four orders of magnitude increase in conductivity values in comparison to pristine 1 – 3 systems. As an example, the conductivity value of 5.86×10?9 S cm?1 (activation energy Ea of 0.60 eV) for 2 at 313 K and 22 % relative humidity (RH) increases up to 2.75×10?5 S cm?1 (Ea of 0.40 eV) for 2@KOH . Moreover, a further increase of conductivity values up to 1.16×10?2 S cm?1 and diminution of Ea down to 0.20 eV is achieved at 100 % RH for 2@KOH . The increased porosity, basicity and hydrophilicity of the 1@KOH – 3@KOH materials compared to the pristine 1 – 3 systems should explain the better performance of the KOH‐modified materials.  相似文献   

19.
The phenylimidorhenium(V) complexes [Re(NPh)X3(PPh3)2] (X = Cl, Br) react with the N‐heterocyclic carbene (NHC) 1,3‐diethyl‐4,5‐dimethylimidazole‐2‐ylidene (LEt) under formation of the stable rhenium(V) complex cations [Re(NPh)X(LEt)4]2+ (X = Cl, Br), which can be isolated as their chloride or [PF6]? salts. The compounds are remarkably stable against air, moisture and ligand exchange. The hydroxo species [Re(NPh)(OH)(LEt)4]2+ is formed when moist solvents are used during the synthesis. The rhenium atoms in all three complexes are coordinated in a distorted octahedral fashion with the four NHC ligands in equatorial planes of the molecules. The Re–C(carbene) bond lengths between 2.171(8) and 2.221(3) Å indicate mainly σ‐bonding between the NHC ligand and the electron deficient d2 metal atoms. Attempts to prepare analogous phenylimido complexes from [Re(NPh)Cl3(PPh3)2] and 1,3‐diisopropyl‐4,5‐dimethylimidazole‐2‐ylidene (Li?Pr) led to a cleavage of the rhenium‐nitrogen multiple bond and the formation of the dioxo complex [ReO2(Li?Pr)4]+.  相似文献   

20.
Coordination polymers (CPs) have been widely studied because of their diverse and adjustable topologies and wide‐ranging applications in luminescence, chemical sensors, magnetism, photocatalysis, gas adsorption and separation. In the present work, two coordination polymers, namely poly[(μ5‐benzene‐1,3,5‐tricarboxylato‐κ6O1:O1′:O3:O3:O5,O5′){μ3‐1,3‐bis[(1,2,4‐triazol‐4‐yl)methyl]benzene‐κ3N:N′:N′′}di‐μ3‐hydroxido‐dicobalt(II)], [Co2(C9H3O6)(OH)(C12H12N6)]n or [Co2(btc)(OH)(mtrb)]n, (1), and poly[[diaquabis(μ3‐benzene‐1,3,5‐tricarboxylato‐κ3O1:O3:O5)bis{μ3‐1,3‐bis[(1,2,4‐triazol‐4‐yl)methyl]benzene‐κ3N:N′:N′′}tetra‐μ3‐hydroxido‐tetracopper(II)] monohydrate], {[Cu4(C9H3O6)2(OH)2(C12H12N6)2(H2O)2]·H2O}n or {[Cu4(btc)2(OH)2(mtrb)2(H2O)2]·H2O}n, (2), were synthesized by the hydrothermal method using 1,3‐bis[(1,2,4‐triazol‐4‐yl)methyl]benzene (mtrb) and benzene‐1,3,5‐tricarboxylate (btc3?). CP (1) exhibits a (3,8)‐coordinated three‐dimensional (3D) network of the 3,8T38 topological type, with a point symbol of {4,5,6}2{42·56·616·72·82}, based on the tetranuclear hydroxide cobalt(II) cluster [Co43‐OH)2]. CP (2) shows a (3,8)‐coordinated tfz‐d topology, with a point symbol of {43}2{46·618·84}, based on the tetranuclear hydroxide copper(II) cluster [Cu43‐OH)2]. The different (3,8)‐coordinated 3D networks based on tetranuclear hydroxide–metal clusters of (1) and (2) are controlled by the different central metal ions [CoII for (1) and CuII for (2)]. The thermal stabilities and solid‐state optical diffuse‐reflection spectra were measured. The energy band gaps (Eg) obtained for (1) and (2) were 2.72 and 2.29 eV, respectively. CPs (1) and (2) exhibit good photocatalytic degradation of the organic dyes methylene blue (MB) and rhodamine B (RhB) under visible‐light irradiation.  相似文献   

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