Hierarchical MnV2O4 double-layer hollow sandwich nanosheets confined by N-doped carbon layer as anode for high performance lithium-ion batteries.

We realized for the first time the fabrication of the unique hollow sandwich nanosheets structure of MnV 2 O 4 /NC via the PDA assisted heterogeneous contraction effect, which is conducive to the rapid transport of lithium ions, avoiding the accumulation of nanosheets and improving the electrochemical performance. [Display omitted] Binary transition metal oxides, especially vanadate metal oxides, are highly desirable for lithium-ion batteries (LIBs) anode materials due to their low-budget and high theoretical lithium storage capacity. However, low conductivity and poor cycle stability caused by volume changes during charge and discharge limit their grid-scale applications. Herein, a novel spinel MnV 2 O 4 double-layer hollow sandwich nanosheets enclosed in N-doped porous carbon layer (MnV 2 O 4 /NC) was efficiently synthesized in 5 min by microwave-assisted and in-situ pyrolysis the coated polydopamine. MnV 2 O 4 /NC shows the superior performance as anode for LIBs with a specific capacities of 760 mA h g−1 at 1000 mA g−1 and outstanding of cycling stability with a specific capacities of 525.5 mA h g−1 after 1000 cycles even at 5000 mA g−1, respectively, which due to its unique double-layer hollow sandwich microstructure, mixed lithium storage mechanism and in-situ coating of nitrogen-doped carbon layer. [ABSTRACT FROM AUTHOR]