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The structure design strategy for LRO based on the reversible anionic redox and spinel-layered coherent structure is propitious to maintaining high specific capacity and improving the reversible anionic redox and stable cyclic performance of LRO. [Display omitted] • LRO cathode with reversible anionic redox and spinel-layered coherent structure is designed. • The specific capacity and initial Coulombic efficiency are enhanced by the introduction of S-anions. • Stable interface structure and enhanced electrochemical kinetics are realized by the spinel-layered coherent structure. • Improved specific capacity and excellent cyclic stability are revealed in the modified LRO. Initiating effective strategies to improve the reversibility of anionic redox and structural stabilization is crucial to the development and industrial application of Li-rich cathode materials (LRO), which are regarded as the preferred option of the cathode materials for the next-generation lithium-ion battery with high energy density. To remit the unexpected behavior of structural destruction and capacity attenuation, this paper proposes a strategy for maintaining high specific capacity and improving the reversible anionic redox and stable cyclic performance of LRO by introducing the spinel-layered coherent structure and S-anions. Proved by the ex-situ X-ray photoelectron spectroscopy, S-anions can regulate the anionic redox reversibility and thus enhance the reversible discharge capacity and initial Coulombic efficiency. Moreover, the structural stability is greatly improved by the introduction of spinel-layered coherent structure and S-anions in LRO, which has been confirmed by abundant structural characterizations. Besides, the results reveal that the optimized material exhibits a high reversible discharge capacity of 289.52 mAh/g and good cyclic performance with a retention rate of 88.21% after 200 cycles. Evidently, the structure design strategy for LRO based on the reversible anionic redox and spinel-layered coherent structure is a significant exploration, which will bring a new clew for the design of the cathode materials with high-energy–density and excellent electrochemical performance. [ABSTRACT FROM AUTHOR]

[Display omitted] • Polar and conductive titanium carbide is introduced for redox regulation. • Lithium sulfide plays as sulfur source in this study. • Sulfur redox and lithium sulfide precipitation are remarkably promoted. • The electrochemical characteristics of as-prepared batteries are boosted. The lithium-sulfur batteries (LSBs) have attracted more and more attention in recent years owing to its high theoretical energy density, abundant sulfur source and relatively low cost. However, the serious polysulfides shuttle and sluggish sulfur redox kinetics hinder the development and commercial application of high-performance lithium-sulfur batteries. In this paper, the titanium carbide (TiC)-decorated carbon matrix is considered as the mediator, anchor and electrocatalyst for polysulfides redox reaction. It has been proved that the conductive and polar titanium carbide can not only chemisorbs lithium polysulfides via titanium-sulfur (Ti-S) coordination, but also optimize the lithium sulfide (Li 2 S) nucleation/precipitation mechanism for better redox reaction. Especially, the graphene oxide and carbon nanotube matrix (GO-CNT) in this case can act as both host for Li 2 S loading and TiC precipitation. Accordingly, the as-fabricated lithium sulfide-graphene oxide–carbon nanotube-titanium carbide (LS-GO-CNT-TiC) cathode delivers the high initial discharge capacity of 956 mAh g−1 at 0.1C and good rate capability of 508 mAh g−1 at 2C. These results consequently manifest that the conductive and polar matrix of LS-GO-CNT-TiC can perform as a promising cathode of the high performance LSBs. [ABSTRACT FROM AUTHOR]