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Sodium molybdate (Na−Mo−O) wrapped by graphene oxide (GO) composites have been prepared via a simple in‐situ precipitation method at room temperature. The composites are mainly constructed with one dimension (1D) ultra‐long sodium molybdate nanorods, which are wrapped by the flexible GO. The introduction of GO is expected to not merely provide more active sites for lithium‐ions storage, but also improve the charge transfer rate of the electrode. The testing electrochemical performances corroborated the standpoint: The Na−Mo−O/GO composites delivers specific capacities of 718 mAh g−1 after 100 cycles at 100 mA g−1, and 570 mAh g−1 after 500 cycles at a high rate of 500 mA g−1; for comparison, the bare Na−Mo−O nanorod shows a severe capacity decay, which deliver only 332 mAh g−1 after 100 cycles at 100 mA g−1. In view of the cost‐efficient and less time‐consuming in synthesis, and one‐step preparation without further treatment, these Na−Mo−O nanorods/GO composites present potential and prospective anodes for LIBs. [ABSTRACT FROM AUTHOR]

In virtue of high capacity and low manufacturing expense, transition metal carbonates (TMCs) have recently arisen enormous research interests as the anode materials for rechargeable lithium ion batteries (LIBs). However, the low electrical conductivity and unstable cycle performance impeded their further development. In this work, Co-B compounds are surface-engineered for the first time onto the mixed single-phase Mn 0.33 Co 0.67 CO 3 microspheres to accelerate the reaction kinetics and suppress the volume fluctuation of the electrodes during Li+ insertion/extraction. Specifically, Co-B nanoflakes not only function as the robust mechanical bridges between Mn 0.33 Co 0.67 CO 3 primary nanoparticles, but also provide extra pathways for electron/charge transport, both of which facilitate the improvement of electrochemical behaviors. Morever, the synergetic effect between Mn 0.33 Co 0.67 CO 3 and Co-B nanoflakes allow a high flux of Li+ across the interface to provide signifcantly boosted Li+ diffusivity. Impressively, the Mn 0.33 Co 0.67 CO 3 @Co-B electrode delivers a high reversible capacity of 806 mA h g−1 over 500 cycles at a high rate of 1.0 A g−1, demonstrating its superior cycling stability. Therefore, surface engineering of borides may be an effective and promising way to improve the electrochemical behaviors of conversion type anodes like TMCs. Image 1 [ABSTRACT FROM AUTHOR]