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In this work, leaf-like hybrid with Bi 2 O 2 CO 3 nanotubes as the “veins” and graphene sheet as the “laminae” is fabricated via a facile one-pot reaction of bismuth nitrate and graphene oxide in alkaline aqueous solution. With the uniform distribution of Bi 2 O 2 CO 3 nanotubes on the graphene substrate, the obtained Bi 2 O 2 CO 3 -NT/G manifests high specific surface area (90.4 m 2 g −1 ) and large pore volume (0.197 cm 3 g −1 ), which are favorable for the efficient light capturing together with the rapid transfer of mass and charge carriers. In comparison with the pure Bi 2 O 2 CO 3 nanotubes and commercial Bi 2 O 2 CO 3 , Bi 2 O 2 CO 3 -NT/G exhibits much enhanced activity and long-term stability towards the photocatalytic degradation of organic dye pollutant, which is owing to its unique leaf-like structural features. [ABSTRACT FROM AUTHOR]

To enforce the interactions between polyaniline (PANI) and graphene, a facile strategy is developed in this work to fabricate the strongly coupled hybrids of PANI nanofibers and graphene (named as PAGs) by introducing different diamines to functionalize graphene oxide. As the electrode material in a two-electrode supercapacitor (SC), the ethylenediamine-functionalized hybrid (PAG-EDA) deliveries an excellent volumetric specific capacitance of 810 F cm −3 at 5 mV s −1 . The SC also manifests high cycling stability by maintaining 84.4% of the initial capacitance after 10,000 cycles. More importantly, PAG-EDA renders the SC to have both high energy density (92.15 W h kg −1 ) and high power density (182.28 kW kg −1 ), superior to most of the previously reported PANI based SC electrode materials. [ABSTRACT FROM AUTHOR]

Three-dimensional hybrids of cobalt oxide (CoO) and graphene frameworks are fabricated via a facile hydrothermal self-assembly process. By adjusting the time of the hydrothermal treatment, the morphologies of the CoO components can be modified from rods to nanoparticles, which further manifest influences on the electrochemical performance of the hybrids. As the anode in lithium-ion battery, the hybrid loaded with spherical CoO nanoparticles exhibits the highest reversible capacity of 1148 mA h g at 100 mA g for 100 cycles among the three samples. Even at a high current density of 5000 mA g, its reversible capacity is still kept at 600 mA h g, outperforming the reported hybrids of CoO and graphene. [ABSTRACT FROM AUTHOR]

As a novel electrocatalyst for oxygen reduction reaction (ORR), nitrogen-doped graphene aerogel supported cobalt nanoparticles (Co-NGA) is archived by a hybrid-assembly of graphene oxide (GO), o-phthalonitrile and cobalt acetate and the following thermal treatment. The hybrid-assembly process successfully combines the ionic assembly of GO sheets and Co ions with the coordination between o-phthalonitrile and Co ions, which can be converted to nitrogen doped carbon and Co nanoparticles in the pyrolysis process under nitrogen flow. Remarkable features of Co-NGA including the macroporous graphene scaffolds, high surface area, and N/Co-doping effect can lead to a high catalytic efficiency for ORR. As the results, the composites pyrolyzed at 600 °C (Co-NGA 600 ) shows excellent electrocatalytic activities and kinetics for ORR in basic media, which are comparable with those of Pt/C catalyst, together with superior durability. [ABSTRACT FROM AUTHOR]

In this work, a novel soft-hard template method towards the direct fabrication of graphene films on silicon/silica substrate is developed via a tri-constituent self-assembly route. Using cetyl trimethyl ammonium bromide (CTAB) as a soft template, silica (SiO2) from tetramethoxysilane as a hard template, and pyrene as a carbon source, the self-assembly process allows the formation of a sandwich-like SiO2/CTAB/pyrene composite, which can be further converted to high quantity graphene films with a thickness of ~1 nm and a size of over 5 μm by thermal treatment. The morphology and thickness of the graphene films can be effectively controlled through the adjustment of the ratio of pyrene to CTAB. Furthermore, a high nonlinear refractive index n2 of ~10−12 m2 W−1 is measured from graphene/silica hybrid film, which is six orders of magnitude larger than that of silicon and comparable to the graphene from chemical vapor deposition process. [ABSTRACT FROM AUTHOR]