Facile preparation of N-doped MnO/rGO composite as an anode material for high-performance lithium-ion batteries

Abstract

An N-doped MnO/rGO composite (N-MnO/rGO) was successfully fabricated by a one-step hydrothermal method in which histidine and potassium permanganate (KMnO4) reacted in water containing graphene oxide, and the product was then calcinated in a nitrogen (N2) atmosphere. The N-MnO/rGO presents an excellent lithium-storage capability. It shows a high reversible specific capacity of 1020 mA h g−1 at a current density of 200 mA g−1 after 150 cycles and 760 mA h g−1 at a current density of 500 mA g−1 after 200 cycles. Meanwhile, the N-MnO/rGO sample presents a stable rate capability from 100 to 2000 mA g−1. Even at 2000 mA g−1, the electrode delivers 335 mA h g−1, which is higher than the capability for the pure MnO particles and rGO sheets. The outstanding electrochemical performances of the N-MnO/rGO electrodes may be attributed to the combined effect of the rGO with N-doping that can effectively buffer the large volume expansion of the MnO particles and can enhance the transport rates of lithium ions and electrons during lithium cycling.