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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]

β-MnO 2 and δ-MnO 2 submicrospheres with different crystallographic forms were parallelly synthesized via a facile way using MnCO 3 submicrospheres as manganese source and template. Fine observation enclosed that the β-MnO 2 and δ-MnO 2 submicrospheres were composed of nanoparticles and nanosheets respectively. The performances of these samples as cathode for aqueous zinc ion batteries were investigated: the prepared β-MnO 2 and δ-MnO 2 submicrospheres exhibit an initial capacity of 100 and 126 mAh/g and preserve about 99% and 81% of their original capacity over 100 cycles at a current density of 100 mA/g, respectively. It is observed from the galvanostatic charge/discharge profiles that the majority of excess capacity for δ-MnO 2 than β-MnO 2 is contributed by the first discharge step referred to H+ insertion process, as δ-MnO 2 has lower charge transfer resistance and larger diffusion coefficient than β-MnO 2. We ascribe this to the larger layer space of δ-MnO 2 which would benefit for the easily insertion/extraction of hydronium ions. For contrast, the β-MnO 2 encounters a sluggish transportation of hydronium ion along with the breaking of H–H 2 O bond during ion inserting. Image 1 [ABSTRACT FROM AUTHOR]