A flexible graphene/polyaniline hybrid material as a supercapacitor electrode was synthesized by an in situ polymerization-reduction/dedoping-redoping process. This product was first prepared in an ethylene glycol medium, then treated with hot sodium hydroxide solution to obtain the reduced graphene oxide/polyaniline hybrid material. Sodium hydroxide also acted as a dedoping reagent for polyaniline in the composite. After redoping in an acidic solution, the thin, uniform and flexible conducting graphene/polyaniline product was obtained with unchanged morphology. The chemical structure of the materials was characterized by X-ray photoelectron spectroscopy and Raman spectroscopy. The composite material showed better electrochemical performances than the pure individual components. A high specific capacitance of 1126 F g(-1) was obtained with a retention life of 84% after 1000 cycles for supercapacitors. The energy density and power density were also better than those of pure component materials.

Graphene oxide, a single layer of graphite oxide (GO), has been used to prepare graphene oxide/polyaniline (PANI) composite with improved electrochemical performance as supercapacitor electrode by in situ polymerization using a mild oxidant. The composites are synthesized under different mass ratios, using graphite as start material with two sizes: 12 500 and 500 mesh. The result shows that the morphology of the prepared composites is influenced dramatically by the different mass ratios. The composites are proposed to be combined through electrostatic interaction (doping process), hydrogen bonding, and pi-pi stacking interaction. The highest initial specific capacitances of 746 F g(-1) (12 500 mesh) and 627 F g(-1) (500 mesh) corresponding to the mass ratios 1:200 and 1:50 (graphene oxide/aniline) are obtained, compared to PANI of 216 F g(-1) at 200 mA g(-1) by charge-discharge analysis between 0.0 and 0.4 V. The improved capacitance retention of 73% (12 500 mesh) and 64% (500 mesh) after 500 cycles is obtained for the mass ratios 1:23 and 1:19 compared to PANI of 20%. The enhanced specific capacitance and cycling life implies a synergistic effect between two components. This study is of significance for developing new doped PANI materials for supercapacitors.

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Reduced-graphene oxide/molybdenum oxide/polyaniline ternary composites, RGO(MP), for use as electrode materials for high energy density supercapacitors, were firstly synthesized using a one-step method with Mo 3 O 10 (C 6 H 8 N) 2 $2H 2 O and graphene oxide (GO) as precursors. When the mass ratio of Mo 3 O 10 (C 6 H 8 N) 2 $2H 2 O to GO is 8 : 1, the resulting composite RGO(MP) 8 shows excellent electrochemical performance with a maximum specific capacitance of 553 F g À1 in 1M H 2 SO 4 and 363 F g À1 in 1 M Na 2 SO 4 at a scan rate of 1 mV s À1 . Its energy density reaches 76.8 W h kg À1 at a power density of 276.3 W kg À1 , and 28.6 W h kg À1 at a high power density of 10294.3 W kg À1 in H 2 SO 4 . While in Na 2 SO 4 , the energy density achieves 72.6 W h Kg À1 at a power density of 217.7 W kg À1 and 13.3 W h Kg À1 at power density of 3993.8 W kg À1 , respectively. The composite also presents good cycling stability (86.6, 73.4% at 20 mV s À1 after 200 cycles in 1 M H 2 SO 4 and Na 2 SO 4 , respectively).

A novel morphology-controlled strategy has been developed to fabricate sulfonated graphene/polyaniline (SGEP) nanocomposites by liquid/liquid interfacial polymerization. Sulfonated graphene (SGE) sheets were synthesized and used as both a macromolecular acid dopant and substrate for the polymerization of polyaniline (PANI), affording the SGEP nanocomposites. The morphology of PANI in the nanocomposites can be controlled to be either nanorods or nanogranules by varying the synthesis conditions. The morphology of SGEP and the shape of PANI can be tuned by adding an additional dopant and varying the amount of SGE used, and this had a significant influence on the electrochemical performance of the nanocomposites as supercapacitor electrode materials. The SGEP nanocomposite with PANI nanorods exhibited a specific capacitance of 763 F/g with a capacity retention of 96% after 100 cycles and good rate properties. Composites obtained with HCl as an additional acid dopant with two different ratios of SGE to PANI showed higher specific capacitances of 793 and 931 F/g, but lower capacity retention after 100 cycles of 77% and 76%, respectively.

Nowadays excessive consumption of fossil fuels due to population growth and industrial development induced serious energy and environmental crisis. To alleviate the ecological crisis and comply with the ever-increasing energy demand, developingThe electrolyte has been considered as a key factor toward higher energy density for Li-ion and Li-metal batteries. However, conventional electrolytes suffer from uncontrolled interfacial reactions and irreversible decomposition causing performance deterioration and potential safety hazard. Organosilicon compounds have attracted great interest as promising electrolyte components due to facile chemical modifications, low glass transition temperatures (T g ), superior chemical, and thermal stabilities. Considerable investigation efforts have been devoted to developing better overall performance of organosilicon-based electrolytes in the past few years. Herein, the recent research progress of organosilicon-based functional electrolytes for the development of liquid, gel, and solid state electrolytes in Li-ion and Li-metal batteries is summarized. Attention is devoted to various types of organosilicon such as silane, siloxane, polysiloxane, and polyhedral oligomeric silsesquioxanes in terms of molecular design, ionic conductivity, functions shown in batteries, thermal, chemical, electrochemical stability, safety, etc. The feasible strategies are also discussed that may promote the comprehensive electrochemical performances of organosilicon-based electrolytes in different types of electrolytes and batteries. Finally, the challenges facing organosilicon-based electrolytes and proposed their possible solutions are presented alongside promising development directions.

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in Wiley InterScience (www.interscience.wiley.com).An efficient and convenient method for the synthesis of polyfunctionalized 4H-pyrans has been achieved through the one-pot condensation of aromatic aldehydes, malononitrile, and 4-hydroxycoumarin, phenols or active methylene carbonyl compounds such as 1, 3-cyclohexanedione and dimedone in the presence of 1-butyl-3-methyl imidazolium hydroxide ([bmim]OH) as catalyst in aqueous media. This method offers several advantages short reaction time, high yields, and simple procedure.