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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]

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]