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Herein, we propose a solvent-assisted approach for preparing Ni-MOF microflowers with high specific capacitance and excellent rate capability as an electrode material for supercapacitors. The high electrochemical performance of this Ni-MOF is attributed to the fast ion transport and low electrical resistance resulting from its hierarchical flower-like structure, and the capacitance contribution from nickel hydroxide species.

Palladium nanocatalysts supported on commercial fumed silica were synthesized via a convenient liquid method without any external reductant or surfactants. The catalysts were characterized by inductively coupled plasma-mass spectrometry, X-ray powder diffraction and the transmission electron microscope analysis. Then it was applied for Suzuki-Miyaura cross-coupling reactions. It was found that a number of aryl halides were efficiently catalyzed using these catalysts in aqueous-ethanol under relatively mild condition within 0.5h. Further study showed that the catalyst could be recycled up to 10 times without loss of activity.

Diphenyl(benzofurano)(benzothieno)germole (BFBTG) was prepared by the reaction of dilithio(benzothienylbenzofuran) with dichlorodiphenylgermane. Optical, thermal, and electrochemical properties of BFBTG were investigated in comparison with those of bis(benzofurano)germole and bis(benzothieno)germole. It was found that both the HOMO and LUMO levels are gradually raised by replacing the thiophene sulfur atoms by oxygen, one by one. The changes of the LUMO levels was larger than those of the HOMO levels, thus widening the HOMO-LUMO energy gaps. This was readily reproduced by DFT calculations on these molecules.

A series of novel sulfur-containing bent N-heteroacenes were constructed and characterized by NMR and UV/Vis spectroscopy, cyclic voltammetry, and single-crystal X-ray diffraction. By introducing sulfur-containing groups (thio, sulfinyl, and sulfonyl) into bent azaacenes, their electronic delocalization was improved and frontier energy levels were modulated. The target products displayed tunable optical and electronic properties through altering the valence of sulfur and fused length of the azaacenes. For the first time, typical products were utilized as organic field effect transistor materials, affording promising results.

Benzofuran-fused silole and germole derivatives were synthesized by the reactions of dilithiobi(benzofuran) with R2SiCl2 and R2GeCl2, respectively. Dilithiobi(benzofuran) was prepared by treating diiodobi(benzofuran) with n-BuLi. Optical and electrochemical measurements of the resulting bis(benzofurano)metalloles and their DFT calculations indicated that the introduction of a metallole unit enhanced the conjugation of bi(benzofuran) mainly by raising the HOMO energy level, similarly to the case of bis(benzothieno)silole prepared previously. Interestingly, [2+2] dimers were obtained by recrystallization of the bis(benzofurano)metalloles, and the dimers readily reverted to the respective monomers upon dissolving in solvent. The crystal structures of the dimers and the monomers were determined by X-ray diffraction studies.

In order to improve light absorption and promote n-type performance, random copolymerization strategy was employed to afford a series of random terpolymer acceptors with acceptor1-acceptor2-acceptor3 (A1-A2-A3) type backbone. The polymers were synthesized from distannylated electron-deficient bithiophene imide monomer with various electron-deficient dibrominated co-monomers using the typical palladium-catalyzed Stille coupling condensation polymerization. Compared with their parent polymers, these A1-A2-A3 type terpolymer acceptors, particularly the dihexylthieno[3,4-b]pyrazine based terpolymer PBTP, can exhibit good miscibility, appropriate polymer crystallinity, and improved absorption in the long-wavelength region due to the incorporation of a third strong electron-withdrawing acceptor moiety thieno[3,4-b]pyrazine. Benefitting from the noncovalent S⋯N interactions, PBTP possessed a planar skeleton and achieved the highest power conversion efficiency (PCE) of 7.35% in the polymer series when serving as the acceptor material in all-polymer solar cells. These results indicate that the A1-A2-A3 type terpolymer acceptors should be promising candidates for developing high-performance all-polymer solar cells.

Bis(diphenylphosphanyl) bi(benzofurano) (BBFP) and Bis(diphenylphosphanyl) bi(benzothiophene) (BBTP) were synthesized by the reaction of dilithio(benzothienylbenzofuran) or dilithio(benzothienylbenzothiophene) with Diphenylphosphinic chloride, then reduced with trichlorosilane to afford the target. Optical and electrochemical measurements of the products and their DFT calculations revealed that P⋯O noncovalent conformational locks played an important role in constructing highly planar BBFP, while BBTP showed a distorted structure. As a result, the photoluminescence (PL) quantum yields of BBFP measured as solids were 0.25. In contrast, the PL quantum yields of BBTP was too low to be detected.

Dithienogermole-diphthalimide, a new molecule, and dithienogermole-dithiadiazole alternate polymers were synthesized by the solvothermal method. Optical properties and molecular weight were investigated by UV–Vis absorption spectroscopy and Gel Permeation Chromatography. Compared with the results achieved by the previously reported normal heating method, these polymers reported here exhibited similar optical properties and possess higher molecular weight.

To develop new element blocks based on thienopyrroles (DTP) units, bis(benzofurano)pyrrole and hybrid thienopyrrole derivatives were synthesized by Buchwald-Hartwing amination methods. Optical absorption, cyclic voltammetry (CV), single-crystal X-ray diffraction analyses and organic thin-film transistor (OTFT) were employed to investigate the structure-activity relationships of the resulting pyrrole derivatives. It was found that the introduction of a benzofuran unit enhances the planarity and conjugation of heteroacenes leading to strong molecular aggregation and denser π-π stacking, resulting in better charge transport properties with the hole mobility of 0.025 cm2V−1s−1 for the OTFTs.

To make steel exhibit attractive properties as high strength and good ductility, this paper presents a novel one step method for forming-Q&P integration—Hot Stamping-Dynamic Partitioning (HS-DP) process. The proposed HS-DP process is simulated with salt bath heat treatment. The effect of microstructure and mechanical properties in a low-carbon AHSS with different cooling rate of the new process is investigated by using scanning electron microscopy (SEM), X-ray diffraction (XRD) and tensile test methods. Microstructure of the steel subjected to HS-DP treatment is mainly composed of initial quenched martensite phase , final quenched martensite phase and retained austenite phase formed. The impact of retained austenite is also discussed, especially the influence of elongation caused by various retained austenite volume fraction and carbon-content. This experiment illustrates the promising application potential of the hot stamping-dynamic carbon partitioning process.

Siloxene nanosheets were successfully modified with palladium nanoparticles by reducing palladium chloride with hydrazine hydrate. The palladium nanoparticles–siloxene nanosheets as a catalyst for the Mizoroki–Heck reaction exhibited high activity, recoverability and stability. The structural morphology of the catalyst was investigated using transmission electron microscopy. High efficiency of the catalyst was proved in the Mizoroki–Heck reaction after five catalytic recycles. Copyright © 2014 John Wiley & Sons, Ltd.

Dithienogermole-dithienylbenzothiadiazole alternating polymers with high molecular weights were synthesized. Optical properties of the polymers were investigated with respect to UV-Vis absorption spectroscopy, indicating that the polymer electronic states are highly dependent on the molecular weight, and the nature and position of substituents on the dithienylbenzothiadiazole units. Photovoltaic properties of the polymers in bulk heterojunction-type polymer solar cells were also examined as blend films with PC70BM, affording the power conversion efficiencies of 1.04-3.83%.

Donor–acceptor-type alternate polymers composed of dithienometallole (metal=Si or Ge) and pyridinocalcogenadiazole (chalcogen=S or Se) units with the molecular weights of Mn=5700–7400 (Mw/Mn=1.3–1.7) were obtained as black solids by the Stille coupling reactions of the corresponding bis(trimethylstannyl)dithienometallole and dibromopyridinochalcogenadiazole. Ultraviolet-visible absorption spectra of the polymers showed highly red-shifted broad bands centered at 732–745 nm in chlorobenzene solutions. Bulk heterojunction-type polymer solar cells with blend films of the polymers and PC70BM as the active layers were fabricated, and a maximum power conversion efficiency of 3.46% was obtained using the dithienogermole-pyridinothiadiazole polymer. Donor–acceptor-type alternate polymers composed of dithienometallole (metal=Si or Ge) and pyridinocalcogenadiazole (chalcogen=S or Se) units were obtained as black solids, which showed highly red-shifted broad bands centered at 732–745 nm in chlorobenzene. Photovoltaic properties of the polymers were examined as blend films with PC70BM and the maximum power conversion efficiency of 3.46% was obtained.

Pd/C composite was successfully synthesized via a microwave-assisted ionic liquid method. The Pd 2+ was reduced to be Pd 0 and deposited on the carbonization formed from glucose at the same time. Powder X-ray diffraction (XRD) and transmission electron microscopy (TEM) tests were used to investigate the crystalline and morphology of the Pd/C composite. Electrochemical properties of Pd/C electrode were examined by cyclic voltammetry, which showed excellent electro-catalytic activity for methanol oxidation and long-term cycle stability.

A novel type of composite electrode based on hydrous manganese oxide and a single-walled carbon nanotube has been prepared and used in electrochemical capacitors. Cyclic voltammetry, galvanostatic charging/discharging tests and electrochemical impedance measurements were applied to investigate the performance of the composite electrodes with different ratios of hydrous manganese oxide and single-walled carbon nanotube. For comparison, the performance of pure hydrous manganese oxide and pure carbon nanotubes was also studied. In this way, the composite electrode with a 6:4 ratio of hydrous manganese oxide to carbon nanotube was found to be the most promising active material for an electrochemical capacitor, which shows both good capacitance and power characteristics.

Nanocrystalline NiO was synthesized by a simple liquid-phase process. Thermogravimetric and differential thermal analysis (TG–DTA), powder X-ray diffraction (XRD) and transmission electron microscope (TEM) tests were applied to investigate the thermal behavior, morphology and crystalline of the NiO powders. Electrochemical properties of NiO crystalline were examined by cyclic voltammetry. A specific capacitance approximately to 300 F g could be achieved with NiO crystalline in the range of 0.0–0.5 V.

A novel one step method for hot pressing and quench & partition (Q&P) integration – hot Pressing-dynamic partitioning (HP-DP) process is presented, which can be processed by regular hot pressing equipment and process. The HP-DP formed steel is an upgrade of the existing hot pressed steel especially suitable for making high strength components with superior crashworthiness due to better toughness. Corresponding steel sheet based on conventional 22MnB5 is designed and prepared. After that, the physical simulation experiments for HP-DP are carried out on thermal-mechanical simulator. Microstructure of the steel subjected to HP-DP treatment, with a typical Q&P treated feature, is mainly composed of initial quenched martensite phase, final quenched martensite phase and retained austenite phase, which indicate the occurrence of carbon diffusion concomitantly with martensite transformation. Compared with conventional hot pressed samples, the HP-DP samples show both better tensile property especially elongation and impact energy absorption ability. The effect of HP-DP parameters on the stability of retained austenite and mechanical property is also discussed. The paper illustrates the promising application potential of the HP-DP process.

TiO2 nanofibres were synthesized by the hydrothermal method. The result shows that the growth of TiO2 nanofibres is sensitive to the concentration of NaOH and the heating temperature.

Hollow carbon microspheres were synthesized in ionic liquids. Transmission electron microscope (TEM) tests were applied to investigate the morphologies of hollow carbon microspheres. Electrochemical properties of hollow carbon microspheres were examined by cyclic voltammetry and charge–discharge.

Trigonal selenium nanorods have been synthesized by sonicating the mixture of ethylenediamine, selenium powder, and water. The diameter of selenium nanowires can be controlled by the concentration of selenium; the length of selenium nanowires can be controlled by the reaction time.

The reduction of Ni (OH) 2 to ultrafine Ni metal powder under hydrothermal condition with ethylene glycol was investigated. The reduction proceeded gentlly at about 160 °C and did not pollute the e...

A TiO 2 nanotube was prepared by a hydrothermal process. Transmission electron microscope tests showed that the products are uniform straight hollow tubes with the diam around 8 nm and the length over 300 nm. X-ray diffraction measurements indicate that the nanotubes crystallized in anatase TiO 2 . Cyclic voltammetry and galvanostatic charging and discharging tests showed that lithium-ion intercalation/deintercalation occured reversibly in the TiO 2 nanotube electrode, and a high capacity can be obtained. Electrochemical impedance spectra show that Li + ion intercalation occurs below 2.2 V. Around the 1.7 V plateau, the total electrochemical resistance reached a minimum.