N-doped carbon encapsulated porous MnO/Mn3O4 submicrospheres as high- performance anode for lithium-ion batteries

摘要

Although Mn-based composites are promising anode materials for advanced lithium-ion batteries (LIBs) owning to their high theoretical capacity (about 2-4 times of commercial graphite), they have some practical limitations such as poor electronic conductivity and large volume expansion, which leading to poor cycle performance. Herein, we developed a versatile strategy to synthesize porous structured MnO/Mn3O4 submicrospheres encapsulated by N-doped carbon shell (MnO/Mn3O4@NC) through an efficient annealing treatment. The as-prepared MnO/Mn3O4@NC composite delivered an excellent electrochemical performance, including a high reversible capacity of 990 mA h g(-1) at 0.2 A g(-1) over 100 cycles and superior rate capability. The outstanding electrochemical performance of MnO/Mn3O4@NC could be attributed to its porous structure and the well-defined protection by N-doped carbon shell for facilitating the transport of electrons and alleviating the volume expansion.