Uniform Carbon Layer Coated Mn3O4 Nanorod Anodes with Improved Reversible Capacity and Cyclic Stability for Lithium Ion Batteries

摘要

A facile one-step solvothermal reaction route to large-scale synthesis of carbon homogeneously wrapped manganese oxide (Mn3O4@C) nanocomposites for anode materials of lithium ion batteries was developed using manganese acetate monohydrate and polyvinylpyrrolidone as precursors and reactants. The synthesized Mn3O4@C nanocomposites were characterized by X-ray diffraction, field-emission scanning electron microscopy, high resolution transmission electron microscopy, X-ray photoelectron spectroscopy, and Raman spectroscopy. The synthesized tetragonal structured Mn3O4 (space group J41 /amd) samples display nanorodlike morphology, with a width of about 200—300 run and a thickness of about 15—20 nm. It is shown that the carbon layers with a thickness of 5 nm are homogeneously coated on the Mn3O4 nanorods, It is indicated from lithium storage capacity estimation that the Mn3O4@C samples display enhanced capacity retention on charge/ discharge cycling. Even after 50 cycles, the products remains stable capacity of 473 mAh g~(-1), which is as much 3.05 times as that of pure Mn3O4 samples. Because of the low-cost, nonpollution, and stable capacity, the carbon homogeneously coated Mn3O4@C nanocomposites are promising anode material for lithium ion batteries.