A facile one-step solvothermal reaction route to large-scale synthesis of carbon homogeneously wrapped manganese oxide (Mn(3)O(4)@C) nanocomposites for anode materials of lithium ion batteries was developed using manganese acetate monohydrate and polyvinylpyrrolidone as precursors and reactants. The synthesized Mn(3)O(4)@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 Mn(3)O(4) (space group I41/amd) samples display nanorodlike morphology, with a width of about 200-300 nm 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 Mn(3)O(4) nanorods. It is indicated from lithium storage capacity estimation that the Mn(3)O(4)@C samples display enhanced capacity retention on charge/discharge cycling. Even after 50 cycles, the products remains stable capacity of 473 mA h g(-1), which is as much 3.05 times as that of pure Mn(3)O(4) samples. Because of the low-cost, nonpollution, and stable capacity, the carbon homogeneously coated Mn(3)O(4)@C nanocomposites are promising anode material for lithium ion batteries.

We developed a facile one-step route to three-dimensional hybrids with Mn 3 O 4 nanoparticles well and homogeneously embedded within ordered mesoporous carbon (OMC) for lithium ion battery applications. The Mn 3 O 4 /OMC hybrids with good rate capability and cycling stability display a high specific capacity up to 802 mA h g À1 , and a high coulombic efficiency of up to 99.2% even after 50 cycles at a high current density of 100 mA g À1 . This value is 1.6 times higher than the discharge capacity of 512 mA h g À1 for pure ordered OMC materials, and more than 5.4 times higher than the discharge value of 148 mA h g À1 for pure Mn 3 O 4 nanoparticles. The enhanced capacity and cycling performance of the Mn 3 O 4 /OMC hybrids could be attributed to their unique robust three-dimensional composite structure and the synergistic effects between the Mn 3 O 4 nanoparticles and OMC. The ordered mesostructured channels of Mn 3 O 4 /OMC hybrids are expected to buffer well against the local volume change during the Li uptake/removal reactions and thus to enhance the structural stability. The OMC matrix wall with a thickness of <10 nm greatly reduces the solid-state transport length for Li diffusion, and the hierarchical ordered mesoporosity facilitates the liquid electrolyte diffusion into the bulk of the electrode material and hence provides fast conductive ion transport channels for the conductive Li + ions. The improved cycling performance can also be mainly attributed to good electrical contact between the Mn 3 O 4 and OMC in the three-dimensional nanocomposites during phase transformation of Mn 3 O 4 upon lithiation/delithiation that usually leads to capacity fading. This facile strategy can be extended to fabricate other ordered mesoporous carbon-encapsulated metal oxides.

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