Areca-inspired core-shell structured MnO@C composite towards enhanced lithium-ion storage

Abstract MnO based composites are regarded as advanced conversion-type anode materials for lithium-ion batteries (LIBs) due to the low cost and high theoretical specific capacities (∼756 mA h g−1). Nevertheless, the undesirable structural stability and sluggish electrochemical reaction kinetics of the electrode materials lead to poor lithium storage performance. Herein, inspired by the structure of areca, the areca-like core-shell MnO@C composites containing of the MnO core and N-doped porous carbon shell are prepared via a biomass-assisted strategy. The formation mechanism of the MnO@C composites with well-defined core-shell structure are successfully clarified through heterogeneous contraction and carbon pyrolysis processes. As anodes for LIBs, the MnO@C composite delivers superior specific capacities of 915.9 and 218.1 mA h g−1 at 0.1 and 5.0 A g−1, respectively, and maintains outstanding cycling performance over 900 cycles at 1.0 A g−1. More importantly, electrochemical kinetics tests further confirm that the improved LIBs capacity mainly originated from the unique areca-like core-shell structure and self-N doped porous carbon shell.