A novel method is described for fabricating an all‐solid‐state flexible micro‐supercapacitor. The microelectrodes of the supercapacitor are prepared by in situ electrodeposition of polyaniline (PANI) nanorods on the surface of reduced graphene oxide (rGO) patterns that are fabricated by micromolding in capillaries. The morphologies of PANI nanorods could be controlled by the concentration of aniline and the growth time in the electrodeposition process. The micro‐supercapacitor possesses electrochemical capacitance as high as 970 F g−1 at a discharge current density of 2.5 A g−1, as well as good stability, retaining 90% of its initial capacitance after 1700 consecutive cycles for the synergistic effect of these new rGO/PANI nanostructures. The results show that the method could represent a route for translating the interesting fundamental properties of rGO and conducting polymers into technologically viable energy devices. Furthermore, this study might further guide the preparation of functional graphene‐based materials.

The recent discovery of superconductivity with a transition temperature (Tc) at 18 K in Kxpicene has extended the possibility of high-Tc superconductors in organic materials. Previous experience based on similar hydrocarbons, like alkali-metal doped phenanthrene, suggested that even higher transition temperatures might be achieved in alkali-metals or alkali-earth-metals doped such polycyclic-aromatic-hydrocarbons (PAHs), a large family of molecules composed of fused benzene rings. Here we report the discovery of high-Tc superconductivity at 33 K in K-doped 1,2:8,9-dibenzopentacene (C30H18). To our best knowledge, it is higher than any Tc reported previously for an organic superconductor under ambient pressure. This finding provides an indication that superconductivity at much higher temperature may be possible in such PAHs system and is worthy of further exploration.

To explore graphene applications in various fields, the processability of graphene becomes one of the important key issues, particularly with the increasing availability of synthetic graphene approaches, because the direct dispersion of hydrophobic graphene in water is prone to forming agglomerates irreversibly. Here, a facile method is proposed to increase the dispersity of graphene through noncovalent functionalization graphene with a water-soluble aromatic electroactive dye, methylene green (MG), during chemical reduction of graphene oxide (GO) with hydrazine. Atomic force microscopic and UV-vis spectrophotometric results demonstrate that chemically reduced graphene (CRG) functionalized with MG (CRG-MG) is well-dispersed into water through the coulomb repulsion between MG-adsorbed CRG sheets. The electrochemical properties of the formed CRG-MG are investigated, and the results demonstrate that CRG-MG confined onto a glassy carbon (GC) electrode has lower charge-transfer resistance and better electrocatalytic activity toward the oxidation of NADH, in relation to pristine CRG (i.e., without MG functionalization). This method not only offers a facile approach to dispersing graphene in water but also is envisaged to be useful for investigations on graphene-based electrochemistry.

There is great interest in utilization of silicon-containing nanostructures as anode materials for lithium-ion batteries but usually limited by manufacturing cost, their intrinsic low electric conductivity, and large volume changes during cycling. Here we present a facile process to fabricate graphene-wrapped silicon nanowires (GNS@Si NWs) directed by electrostatic self-assembly. The highly conductive and mechanical flexible graphene could partially accommodate the large volume change associated with the conversion reaction and also contributed to the enhanced electronic conductivity. The as-prepared GNS@Si NWs delivered a reversible capacity of 1648 mAh·g(-1) with an initial Coulombic efficiency as high as 80%. Moreover, capacity remained 1335 mAh·g(-1) after 80 cycles at a current of 200 mA·g(-1), showing significantly improved electrochemical performance in terms of rate capability and cycling performance.

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