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A CoO/3D graphene composite synthesized via hydrothermal method was used as an anode material for Li-ion batteries. X-ray diffraction, scanning electron microscopy, thermogravimetry, energy-dispersive X-ray spectroscopy, transmission electron microscope, cyclic voltammetry, electrochemical impedance spectroscopy, and charge/discharge measurement were conducted to evaluate the physical and electrochemical properties of the CoO/3D graphene composite. Results showed that the composite delivered high rate capacities of 1481.1, 657.7, 472.5, 423.8, and 391.2 mAh g −1 , at 50, 100, 200, 300, 400, and 500 mA g −1 , respectively. The capacity after 100 cycles was 860 mAh g −1 at 50 mA g −1 , thereby indicating excellent cycle stability. The excellent electrochemical performance was ascribed to 3D graphene sheets that were formed in the composite structure. [ABSTRACT FROM AUTHOR]

Abstract: Reduced graphene oxide/cadmium sulfide (RGO/CdS) hybrid material was synthesized by a one-step solvothermal method, wherein graphene oxide (GO) was a supporting material on which CdS nanoparticles were distributed homogeneously, and cadmium acetate (Cd(Ac)2·2H2O) was used as the CdS precursor. The supporting material RGO for CdS nanoparticles effectively enhanced their photocatalytic activities for the photodegradation of methylene blue in the aqueous solution. The optimum weight ratio of the GO to CdS in the hybrid material was 5.0%, which exhibited an excellent photodegradation efficiency (94%) and a better removal efficiency of total organic carbon (TOC) (57%), about 2.5 times and 5.1 times higher than that of pure CdS nanoparticles, respectively, under visible light (VL) irradiation. This improved photodegradation efficiency could be attributed to the increased adsorbability for methylene blue molecules, light absorption levels located in visible region, high charge transfer and separation ability, due to the introduction of a two-dimensional RGO network. [Copyright &y& Elsevier]