3D plum candy-like NiCoMnO(4)@graphene as anodes for high-performance lithium-ion batteries

3D plum candy-like NiCoMnO(4) microspheres have been prepared via ultrasonic spraying and subsequently wrapped by graphene through electrostatic self-assembly. The as-prepared NiCoMnO(4) powders show hollow structures and NiCoMnO(4)@graphene exhibits excellent electrochemical performances in terms of rate performance and cycling stability, achieving a high reversible capacity of 844.6 mA h g(−1) at a current density of 2000 mA g(−1). After 50 cycles at 1000 mA g(−1), NiCoMnO(4)@graphene delivers a reversible capacity of 1045.1 mA h g(−1) while the pristine NiCoMnO(4) only has a capacity of 143.4 mA h g(−1). The hierarchical porous structure helps to facilitate electron transfer and Li-ion kinetic diffusion by shortening the Li-ion diffusion length, accommodating the mechanical stress and volume change during the Li-ion insertion/extraction processes. Analysis from the electrochemical performances reveals that the enhanced performances could be also attributed to the reduced charge-transfer resistance and enhanced Li-ion diffusion kinetics because of the graphene-coating. Moreover, Schottky electric field, due to the difference in work function between graphene and NiCoMnO(4,) might be favorable for the redox activity of the NiCoMnO(4). In light of the excellent electrochemical performance and simple preparation, we believe that 3D plum candy-like NiCoMnO(4)@graphene composites are expected to be applied as a promising anode materials for high-performance lithium ion batteries.