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Abstract: Graphene composites were prepared by hydrothermal method using titanium dioxide (TiO2) adsorbed graphene oxide (GO) sheets as precursors. Free-standing hybrid films for lithium-ion batteries were prepared by adding TiO2/graphene composites to the polyvinylidene fluoride (PVdF)/N-methyl-2-pyrrolidone (NMP) solution, followed by a solvent evaporation technique. These films were characterized by atomic force microscopy (AFM), X-ray diffraction (XRD), scanning electron microscopy (SEM) and various electrochemical techniques. Flexible films show an excellent cycling performance, which was attributed to the interconnected graphene conducting network, which depressed the increasing of electric resistance during the cycling. [Copyright &y& Elsevier]

Abstract: Bi0.4Ca0.6MnO3 (BCMO) film was epitaxially grown on a (110) SrTiO3 substrate using the pulsed laser ablation technique. The morphologies of the epitaxial films with different thicknesses were considerably different. For the Bi0.4Ca0.6MnO3 epitaxial film with a thickness of 10nm, the morphology was more like islands. As the film thickness increased to 40nm, the island became smaller, and disappeared when the film thickness reached 110nm. The growth mechanism of the epitaxial films depends on film thickness, which has been discussed. The results will shed light on the formation mechanism of BCMO epitaxial films. [Copyright &y& Elsevier]

Abstract: Bi0.4Ca0.6MnO3 (BCMO) film with a thickness of 110nm was epitaxially grown on a (110) SrTiO3 (STO) substrate using pulsed laser ablation technique. The microstructure of the epitaxial films was investigated by transmission electron microscopy (TEM) and high-resolution transmission electron microscopy (HRTEM) in details. Two different kinds of dislocations, one being perpendicular to the BCMO/STO interface, the other being parallel to the interface, have been commonly observed. The formation mechanism for these dislocations has been discussed. All the dislocations are thought to relieve the local strain in the epitaxial film. [Copyright &y& Elsevier]

Structure and optical of polycrystalline NiO films fabricated by reactive sputtering and its resistive switching properties in Au/NiO/Pt structures are investigated. The size of surface uniform pyramid-like islands and average surface roughness increase with the increase of NiO film thickness ( t ). The NiO films grow with the preferred (111) orientation at 400 °C, but both (100) and (110)-oriented grains exist in the films fabricated at room temperature. Raman results reveal that the crystallinity of the films fabricated at 400 °C becomes good by comparing with that at room temperature. The optical band gap monotonically decreases from 4.44 eV at t =22 nm to 3.55 eV at t =800 nm. The resistance of the Au/NiO/Pt/Ti/glass structures could be switched between two stable states including low and high resistance states. The bipolar endurance performance of the resistive switching remains nondegradable after 200 cycles. The resistive switching can be ascribed to the carrier trapping and detrapping induced by the electric field, which can change the thickness of the depletion layer at Au/NiO interface. [ABSTRACT FROM AUTHOR]