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An ordered mesoporous carbon (OMC) with a nanorod-shaped morphology and enhanced graphitic character was employed as an ideal support for MnO x (major phase of Mn 3 O 4 with a small portion of MnO) nanocrystals which possess a high theoretical conversion capacity as a Li-ion battery anode. The MnO x /OMC nanocomposite was prepared by a simple wet-impregnation of Mn(NO 3 ) 2 aqueous solution onto OMC nanorods followed by thermal treatment at 450 C in an Ar flow. The electrochemical properties of MnO x /OMC were investigated in comparison to those of bare OMC and a commercial graphite as an anode for Li-ion batteries. Transmission electron microscopy, scanning electron microscopy, X-ray diffraction, N 2 adsorption-desorption analysis, X-ray photoelectron spectroscopy, and thermogravimetric analysis revealed that 3-30 nm MnO x nanocrystals at a high loading of 68.4 wt% were formed and well dispersed in the pore structure of OMC nanorods. The MnO x /OMC exhibited a high reversible capacity (>950 mAh g À1 ) after 50 deep charge-discharge cycles with excellent cycling stability, Coulombic efficiency and rate capability. As an anode for Li-ion batteries, the incorporation of insulating high density MnO x nanocrystals into OMC nanorods showed synergistic benefits of high volumetric capacity as well as specific capacity, and small redox voltage hysteresis compared to OMC nanorods. † Electronic supplementary information (ESI) available: Small angle XRD and BET measurements of samples, voltage profiles of graphite, measurement of electrode coating densities, SEM images of electrode cross-sections, and rate performance of graphite. See

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A new synthesis strategy for ordered mesoporous carbon with precisely controllable pore sizes in the range of 3 to 10 nm using an inorganic pore expanding agent is demonstrated. The synthesis mechanism involves the formation of borosilicate and boron oxide nanolayers between carbon framework and silica surface within the mesopores of the silica template caused by spontaneous phase separation and subsequent solid state reaction during carbonization.

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