Hydrothermal synthesis of core-shell Mn3O4@C microspheres as superior anode materials for high-performance lithium-ion storage

Abstract

The Mn3O4@C microspheres were prepared by combining a low temperature coating method of one-step hydrothermal process and subsequently annealing treatment. In this method, the resorcinol and formaldehyde (RF) were applied as carbon source to enhance the electrical conductivity of Mn3O4 microspheres. The resulting core-shell Mn3O4@C microspheres comprised of irregular aggregated nanoparticles with an average diameter of approximately 2 μm. The Mn3O4 microspheres were homogeneously coated by the carbon layers with a thickness of 50 nm. The Mn3O4@C microspheres exhibit dramatically excellent reversible discharge capacity of 913.8 mAh/g at 0.5 A/g after 300 cycles with an outstanding rate capability. The discharge capacity of Mn3O4@C microspheres could maintain up to 992 mAh/g even after 800 cycles at 1 A/g. The improved electrochemical performance of the synthesized Mn3O4@C microspheres is attributed to the fact that the carbon-shell structure can effectively buffer volume change, maintain structure integrity and improve electrical conductivity. The Mn3O4@C microspheres could be utilized as a promising candidate as the anode material for lithium-ion batteries.