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Currently, lithium-sulfur batteries suffer from several critical limitations that hinder their practical application, such as the large volumetric expansion of electrode, poor conductivity and lower sulfur utilization. In this work, TiO 2 nanofibers with mesoporous structure have been synthesized by electrospinning and heat treating. As the host material of cathode for Li-S battery, the as prepared samples with novelty structure could enhance the conductivity of cathode composite, promote the utilization of sulfur, and relieve volume expansion for improving the electrochemical property. The initial discharge capacity of TiO 2 /S composite cathode is 703 mAh/g and the capacity remained at 652 mAh/g after 200 cycles at 0.1 C, whose the capacity retention remains is at 92.7%, demonstrating great prospect for application in high-performance Li-S batteries. which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made.

To meet practical application needs, high-massloading lithium−sulfur (Li−S) batteries are urgently needed for achieving good electrochemical performance. Here, unique threedimensional (3D) reduced graphene oxide (rGO)-coated ultrathin zinc−cobalt oxide composite N-doped carbon self-supporting stratified porous nanosheet arrays, anchored on flexible carbon cloths (CCs) (rGO-S/ZnCo 2 O 4 @NC/CCs), are designed and chosen as independent cathodes. A lithium−sulfur battery using rGO-S/ZnCo 2 O 4 @NC/CC as the cathode exhibits a high capacity of around 1377.8 mAh g −1 and retains an outstanding capacity of around 1006.3 mAh g −1 after 700 cycles at 0.1 C with a sulfur loading of 2.2 mg cm −2 . Moreover, even under a high sulfur load of 8.2 mg cm −2 , a superior capacity of 735.9 mAh g −1 can be achieved at 0.1 C. In this work, a special function and a 3D self-supporting stratified porous nanostructure with a conductive rGO coating have been designed, which reasonably alleviate the "shuttle effect" of high-load Li−S batteries through the "internal and external double repair" action.

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Conversion-type NiO material is attractive due to its high theoretical capacity, and yet it displays inadequate reaction sites, a huge volume expansion, and a sluggish ions/electrons’ transport rate in the lithium-ion battery (LIB) tests. In this work, metal organic framework (MOF) template and reduced graphene oxide (rGO) are employed to prepare hollow Co–La-doped NiO nanocubes/rGO nanocomposite. The design of a hollow nanocubes frame together with rich rough nanosheets could both provide abundant active sites and alleviate volume change during the lithiation/delithiation reaction. The conductive rGO network can not only significantly improve the electron transport of metallic oxide, but can also serve as a separator to inhibit the agglomeration of nanostructures. The doping of Co and La elements regulates the component of NiO structure and optimizes the ions/electrons’ transport rate. Applied to the LIB anode material, this nanocomposite harvests a nice specific capacity (first discharge capacity of 1279.6 mAh g–1 and average capacity of 726.9 mAh g–1 at 0.1 A g–1). Besides, after 500 repeated cyclic tests at a high current density of 1 A g–1, the specific capacity still retains 434.1 mAh g–1. Structural characterization and electrochemical analysis well disclose that the significantly enhanced electrochemical performance is benefited from a distinct hollow structure, regulation of La content, and incorporation with rGO, which further highlights the suitable structural design and composition regulation.