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Abstract: A NiO–graphene hybrid film with 3D hierarchically porous structure has been rationally designed and constructed through a series of controlled fabrication processes. Multilayered porous graphene sheet network with the pore size of several micrometers is created via a so-called “on-water spreading” method, which is facile, economical, efficient and scalable. Then, the cross-like NiO nanoflakes film is uniformly grown onto the porous graphene sheet framework by a chemical bath deposition. The NiO–graphene hybrid film exhibits specific capacitance of 540 F g−1 at 2 A g−1 with 80% capacitance retention after 2000 cycles in 2 M KOH aqueous solution, which is much higher than that achieved from the bare NiO nanoflakes film (370 F g−1, with 66% capacitance retention). Moreover, chronoamperometry and electrochemical impedance spectroscopy measurements reveal that the NiO–graphene hybrid demonstrates enhanced reaction kinetics with about only 50% of respond time for NiO/NiOOH reaction and 79% of charge-transfer resistance compared with those of the bare NiO film. The proposed strategy could offer an effective way to fabricate graphene-based electrode materials for applications in various energy-storage devices. [Copyright &y& Elsevier]

Scrupulous design and fabrication of advanced anode materials are of great importance for developing high-performance lithium ion batteries. Herein, we report a facile strategy for construction of free-standing and free-binder 3D porous carbon coated MoS 2 /nitrogen-doped graphene (C-MoS 2 /N-G) integrated electrode via a hydrothermal-induced self-assembly process. The preformed carbon coated MoS 2 is strongly anchored on the porous nitrogen-doped graphene aerogel architecture. As an anode for lithium ion batteries, the C-MoS 2 /N-G electrode delivers a high first discharge capacity of 1600 mAh g −1 and maintains 900 mAh g −1 after 500 cycles at a current density of 200 mA g −1 . Impressively, superior high-rate capability is achieved for the C-MoS 2 /N-G with a reversible capacity of 500 mAh g −1 at a high current density of 4000 mA g −1 . Furthermore, the lithium storage mechanism of the obtained integrated electrode is investigated by ex-situ X-ray photoelectron spectroscopy and transmission electron microscopy in detail. [ABSTRACT FROM AUTHOR]