Sb-based nanocomposites are attractive anode materials for batteries as they exhibit large theoretical capacity and impressive working voltage.However,tardy potassium ion diffusion characteristics,u nstable Sb/electrolyte interphase, and huge volume variation pose ac hallenge,h indering their practical use for potassium-ion batteries (PIBs). Now,asimple robust strategy is presented for uniformly impregnating ultrasmall Sb nanocrystals within carbon nanofibers containing an arrayo fh ollown anochannels (denoted u-Sb@CNFs), resolving the issues abovea nd yielding high-performance PIBs. u-Sb@CNFs can be directly employed as an anode,t hereby dispensing with the need for conductive additives and binders. Such aj udiciously crafted u-Sb@CNF-based anode renders as et of intriguing electrochemical properties,r epresenting large charge capacity,u nprecedented cycling stability,a nd outstanding rate performance.Areversible capacity of 225 mAh g À1 is retained after 2000 cycles at 1Ag À1 .

Developing efficient anode materials for sodium-ion batteries (SIBs) is important for the storage of renewable energy. Inspired by the rapid development of biomass-derived hard carbons and heteroatom-doped carbon materials in various areas, a high-temperature sulfurizing method is exploited for the fabrication of sulfur-doped carbon microtubes (S-CMTs). Owing to high sulfur doping (10.2 wt %) and well-developed microporous structure, the as-prepared S-CMTs show a large charge capacity of 532 mAh g −1 at a current rate of 200 mA g −1 , outstanding rate capability (234 mAh g −1 at 2 A g −1 ), and exceptional cycling stability (281 mAh g −1 after 1000 cycles at 1 A g −1 ), values that are superior to those of biomass-derived carbons reported previously. The excellent electrochemical performance of S-CMTs in full cells paired with N,B-co-doped carbon-coated Na 3 V 2 (PO 4 ) 3 cathodes further demonstrates the feasibility of SIBs. The simple synthesis strategy can potentially be extended to other carbon-based anode materials for sodium-ion batteries.

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This review summarizes the template-free synthesis of some metal oxide hollow micro-/nanospheres based on Ostwald ripening for lithium-ion batteries.

MoS 2 has attracted a lot of attention for electrochemical energy storage. Herein, we design and fabricate unusual hierarchical composite nanospheres by cultivating a MoS 2 sheet-like nanostructure on nitrogendoped carbon polyhedra (designated as CP@MoS 2 nanospheres). The nitrogen-doped carbon polyhedra are able to significantly boost the electrical conductivity of the hybrid architecture and largely mitigate the agglomeration of the MoS 2 nanostructure. The sheet-like MoS 2 nanostructure can render a great deal of storage sites toward lithium and sodium. When measured as a negative electrode for Li storage, these CP@MoS 2 nanospheres manifest a large charge capacity of approximately 549 mAh g −1 , a superior cycle life of 900 cycles, and excellent rate property. Furthermore, they also demonstrate improved electrochemical activity for Na + ion storage.