•CoMoO4/Co9S8 nanorod arrays on Ni foam was synthesized by hydrothermal route.•CoMoO4/Co9S8 exhibited a superior capacitance of 9.17 F cm−2 (2059.26 F g−1).•A high energy density was equal to 42 Wh kg−1 for an asymmetric design.CoMoO4/Co9S8 nanorod arrays supported on nickel foam are successfully assembled via a facile two-step hydrothermal route. Due to the unique nanorod array structure, the CoMoO4/Co9S8, as the electrode, possesses a high capacity 1.54 mA h·cm−2 (343.21 mA h·g−1) and a large capacitance 9.17 F cm−2 (2059.26 F g−1) at a current density of 20 mA·cm−2 (4.44 A·g−1), and an excellent cycling stability (8.6% degradation after 3000 cycles). The asymmetric supercapacitor based on the CoMoO4/Co9S8 nanorod arrays as a positive electrode and porous active carbon as a negative electrode in an alkaline KOH aqueous electrolyte is fabricated. Owing to the synergetic effect between CoMoO4/Co9S8 and active carbon, CoMoO4/Co9S8//active carbon asymmetric supercapacitor exhibits an outstanding energy density of 42 Wh·kg−1 and an excellent cycling stability with 89.5% specific capacitance retained after 5000 cycles in an operating voltage of 1.6 V. The facile synthesis route and remarkable supercapacitive performance of the CoMoO4/Co9S8 nanorod arrays is promising as a positive electrode materials for high-performance asymmetric supercapacitors.Download high-res image (194KB)Download full-size image

Mesoporous TiO2 microsphere (MTM) was synthesized via a simple solution route and then mixed with commercial TiO2 (P25) to form highly homogeneous and stable TiO2 colloid by simple hydrothermal treatment. The TiO2 colloid was coated onto the plastic conductive substrate to prepare mesoporous TiO2 film for flexible dye-sensitized solar cells (DSSCs) by low-temperature heat treatment. The influence of MTM content on the physicochemical properties of the flexible TiO2 film was characterized by scanning electron microscope, transmission electron microscopy, X-ray diffraction, energy-dispersive X-ray spectrometer, N2 adsorption-desorption isotherms, UV-vis absorption and diffuse reflectance spectra. It is revealed that with increasing the MTM content, the dye-loading capability of TiO2 film and light-harvesting efficiency of flexible DSSCs are improved due to MTM having high surface area and acting as a light scattering center, respectively, resulting in the enhancement of photocurrent of flexible DSSCs. However, more and larger cracks having negative effect on the performances of flexible DSSCs are formed simultaneously. Under the optimal condition with MTM content of 20%, a flexible DSSC with overall light-to-electric energy conversion efficiency of 2.74% is achieved under a simulated solar light irradiation of 100 mW cm−2 (AM 1.5), with 26% improvement in comparison with DSSCs based on P25 alone.

Two unusual pillared-layer 3d–4f Ln–Cu heterometallic coordination polymers, {[Ln2Cu5Br4(IN)7(H2O)6]·H2O}n (Ln=Eu (1) and Gd (2), HIN=isonicotinic acid), have been synthesized under hydrothermal conditions, and characterized by elemental analysis, IR, thermal analysis and single-crystal X-ray diffraction. The structure determination reveals that 1 and 2 are isostructural and feature a novel three-dimensional pillared-layer hetrometallic structure built upon the linkages of one-dimensional (1D) linear Ln–carboxylate chains, zero-dimensional (0D) Ln–carboxylate Ln2(IN)8 dimers, rare 1D zigzag [Cu5Br4]n inorganic chains and IN− pillars. In both 3D structures, there are Ln–carboxylate layers resulted from the connections of 1D Ln–carboxylate chains and 0D Ln2(IN)8 dimers through O–H⋯O hydrogen bondings. The luminescent properties of 1 have been investigated. The magnetic properties of 1 and 2 have also been studied.Graphical abstractTwo unusual pillared-layer Eu (Gd)–Cu heterometallic coordination polymers have been hydrothermally synthesized. The luminescent properties of Eu–Cu compound and magnetic properties of both compounds are investigated.Highlights► Two unusual 3D pillared-layer Eu (Gd)–Cu heterometallic coordination polymers have been synthesized. ► 1D and 0D Ln–carboxylate motifs construct layers by O–H⋯O hydrogen bondings. ► In both the structures, there are rare 1D zigzag Cu/Br inorganic chains. ► Luminescent properties of Eu–Cu compound and magnetic properties of both the compounds are investigated.

An unusual three-dimensional (3D) pillared-layer 3d–4f (Cu+–Sm3+) heterometallic coordination polymer, {Sm2Cu7Br6(IN)7(H2O)5·3H2O}n (1) (HIN = isonicotinic acid), has been successfully synthesized by hydrothermal reaction of Sm2O3, CuBr2, HIN, HClO4 and H2O, and characterized by elemental analyses, IR, PXRD, and single-crystal X-ray diffraction. The structure determination reveals that 1 possesses 3D heterometallic framework constructed upon unprecedented [Cu7Br6]nn+ inorganic layers linked by dimeric Sm2(IN)6 pillars. Additionally, the thermogravimetric analysis and luminescent property of 1 were investigated and discussed.The {Sm2Cu7Br6(IN)7(H2O)5·3H2O}n is the first example of 3D 3d–4f heterometallic coordination polymer based on 2D Cu–Br inorganic layers.Research Highlights► A novel 3D Sm–Cu coordination polymer based on 2D Cu-Br layers has been synthesized. ► CuBr2N triangles and CuBr3N tetrahedra construct the unprecedented 2D Cu-Br layer. ► This compound exhibits good luminescent property.

Two new 4d–4f Ln–Ag heterometallic coordination polymers, {[Ln3Ag5(IN)10(H2O)7]·4(ClO4)·4(H2O)}n (Ln=Eu (1) and Sm (2), HIN=isonicotinic acid), have been synthesized under hydrothermal conditions by reactions of Ln2O3, AgNO3, HIN and HClO4, and characterized by elemental analysis, IR, thermal analysis and single-crystal X-ray diffraction. It is proved that HClO4 not only adjusts the pH value of the reaction mixture, but also acts as anion template. The structure determination reveals that 1 and 2 are isostructural and feature a novel two-dimensional (2D) layered hetrometallic structure constructed from one-dimensional Ln–carboxylate chains and pillared Ag(IN)2 units. The 2D layers are further interlinked through Ag⋯Ag and Ag⋯O(ClO4−) multiple weak interactions, which form a rare Ag–ClO4 ribbon in lanthanide–transition metal coordination polymers, to give rise to a three-dimensional supramolecular architecture. Moreover, the luminescent properties of these two compounds have also been investigated at room temperature.Graphical abstractTwo new anion-templated 2D 4d–4f Ln–Ag heterometallic coordination polymers based on novel lanthanide–carboxylate chains and pillared Ag(IN)2 units, {[Ln3Ag5(IN)10(H2O)7]·4(ClO4)·4(H2O)}n (Ln=Eu (1) and Sm (2), HIN=isonicotinic acid), have been hydrothermally synthesized and structurally characterized. 1 and 2 exhibit good luminescent properties.Research highlights► Two 2D Eu (Sm)–Ag coordination polymers templated by perchlorate anion have been synthesized. ► Polymers consist of novel 1D lanthanide–carboxylate chains. ► In both structures, there are rare Ag⋯Ag and Ag⋯O(ClO4−) multiple weak interactions.► Both compounds exhibit good luminescent properties.

A novel three-dimensional (3D) pillared-layer 3d–4f lanthanum-copper heterometallic coordination polymer, {La2Cu7I6(IN)7(H2O)6·2H2O}n (1) (HIN = isonicotinic acid), has been synthesized by hydrothermal reaction of La2O3, CuI, HIN with HNO3, and characterized by elemental analyses, IR, PXRD, and single-crystal X-ray diffraction. The structure determination reveals that the 3D framework of 1 is constructed upon [Cu7I6]nn+ inorganic layers linked by dimeric La2(IN)6 pillars. Additionally, the thermogravimetric analysis and luminescent property of 1 were investigated and discussed.

A new trinuclear magnetic lead iodide semiconductor PbI4[Cu(Me2dtc)(bipy)]2 (Me2dtc = N,N-dimethyldithiocarbamate, bipy = 2,2′-bipyridine) has been synthesized, and structurally characterized by single-crystal X-ray diffraction. It crystallizes in the monoclinic space group P21/c with a = 22.2137(11) Å, b = 11.3687(4) Å, c = 15.3382(8) Å, β = 102.372(3)°, Z = 4, V = 3783.6(3) Å3. It is built up by [PbI4S2] octahedron linked with two [CuIS2N2] square pyramids through common edges. The adjacent molecules stack with each other to form a two-dimensional (2D) layer along ab plane via the π–π stacking interactions between aromatic groups of bipy ligands. Then the 2D layers are further extended into a three-dimensional structure through hydrogen bonding interactions. The temperature dependence of the electrical conductivity indicates that this compound exhibits semiconducting character. The title brown–black compound has an optical bandgap of 1.26 eV, and the variable-temperature magnetic susceptibility measurement indicates weak antiferromagnetic behavior with J = −1.06 cm−1.