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Flower-like ZnO–NiO mesoporous architectures were synthesized through annealing the zinc hydroxide carbonate–nickel hydroxide carbonate composite precursor, which was prepared via a one-pot hydrothermal route. More importantly, we successfully prepared flower-like porous ZnO–NiO/graphene composites by introducing flexible graphene into the flower-like porous ZnO–NiO. In addition, we explore the application of the 3D flower-like ZnO–NiO composite mesoporous architectures and flower-like porous ZnO–NiO/graphene composites as anode materials for lithium ion battery. Electrochemical study presented that the as-prepared flower-like porous ZnO–NiO/graphene composites demonstrate excellent electrochemical performance and cycling stability. The first discharge capacity is 1205.7 mA h/g at a high current density of 300 mA/g. After 50 cycles, the reversible capacity is 452.7 mA h/g at a current density of 300 mA/g and the coulomb efficiency reaches at 99%.The improved electrochemical performances are mainly attributed to its morphological characteristics of mesoporous, nanosheet self-assembling architectures, as well as the addition of graphene. These results suggest that such 3D flower-like porous ZnO–NiO/graphene composites are promising materials for lithium ion battery. [ABSTRACT FROM AUTHOR]

Three-dimensional (3D) graphene@CNTs@MnO 2 (GCM) nanocomposites materials have been fabricated by a facile two-step method. The structure, morphology and electrochemical properties of the 3D nanocomposites were investigated by XRD, TG, Raman, SEM, TEM and electrochemical measurements. The 3D forest-like rGO@CNTs (GC) serves as both the backbone and ideal electron pathway for MnO 2 . With this sophisticated configuration, the 3D GCM nanocomposites exhibit a specific capacitance of 245 F g −1 at 0.5 A g −1 , excellent cycling stability (91.4% retention after 2000 cycles at 1 A g −1 ) and high rate capability. These excellent capacitive performances may make the as-prepared nanocomposites as promising electrode materials for supercapacitors. [ABSTRACT FROM AUTHOR]