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Lithium–sulfur batteries are more promising and attractive than lithium‐ion batteries owing to a higher charge‐storage capacity. However, their commercial applications are hindered by an undesirable polysulfide shuttling effect during the cycling procedure. Herein, nitrogen and sulfur codoped carbon nanotubes intertwined with flower‐like molybdenum disulfide (NSCNTs/MoS2) were synthesized by using a feasible hydrothermal method and used as effective lithium polysulfides (LiPSs) tamers. The NSCNTs/MoS2 had a strong hybrid structure with strong interfacial interactions for physical confinement, chemical adsorption, and electrocatalytic conversion of intermediate LiPSs during the charge–discharge process. The NSCNTs intensified the flexibility and constructed a conductive framework for rapid ion/electron transfer, whereas the electrocatalysis of MoS2 managed the sulfur reaction chemistry in two ways: it chemically immobilized LiPSs through Li−S bonds and kinetically sped up the sulfur redox reactions. Owing to these merits, the Li–S cell with a NSCNTs/MoS2 host and NSCNTs/MoS2‐coated separator (NSCNTs/MoS2/S‐NM) exhibited a high reversible capacity of 814 mAh g−1 at 1.0 C and long‐lasting cycling durability with an ultralow capacity decay of 0.02 % per cycle over 1000 cycles. Accordingly, rationally integrating the concepts of physical immobilization, chemical capture, and electrocatalysis to establish a multifaced cell structure for the architecture of high‐performance Li–S batteries is a significant strategy. [ABSTRACT FROM AUTHOR]

A kind of yarn‐like nitrogen‐doped carbon nanotubes microsphere (NSCNT) is synthesized in one‐step synthesis, and sulfur is added by melting immersion to form carbon nanotube microspheres/sulfur composites (NSCNT/S). The morphology, structure and electrochemical property of the obtained NSCNT/S are explored by field‐emission scanning electron microscopy (FESEM), X‐ray diffraction (XRD) and electrochemical tests. The results show that NSCNT possesses a high N content and unique mesoporous carbon framework with large specific surface area of 1029 m2 g−1, which can not only favor rapid electron and Li‐ion transfer but also effectively mitigate dissolved polysulfides via strong chemical and physical adsorption. Due to the synergetic interaction of NSCNT, the NSCNT/S delivers a high initial discharge capacity of 1241.3 mAh g−1 at 0.1 C and large rate capacity of 1175.5 mAh g−1 at 1 C with ultralow capacity decay of 0.1 % per cycle and high areal mass loading of 3.1 mg cm−2. This eco‐friendly NSCNT/S can offer an appealing improvement for the applications of high‐performance lithium‐sulfur batteries. Playing with a yarn ball: yarn‐like nitrogen‐doped carbon nanotube microspheres (NSCNT) are synthesized following a one‐step approach. Sulfur is added by melting immersion to form composites (NSCNT/S). The morphology, structure and electrochemical properties of the obtained NSCNT/S are explored. High discharge capacity and large rate capacity render this eco‐friendly NSCNT/S as an appealing improvement for the applications of high‐performance lithium‐sulfur batteries. [ABSTRACT FROM AUTHOR]

Li1.1V0.9O2/C microspheres with isomeric core‐shell structure were synthesized by a rapid cooling and subsequent evaporative assembly approach. The prepared Li1.1V0.9O2/C microspheres were characterized by X‐ray diffraction (XRD), Raman spectroscopy, scanning electron microscopy (SEM) including elemental mapping analysis, and transmission electron microscopy (TEM). The core‐shell Li1.1V0.9O2/C microspheres display identical composition but distinct texture of cores and shells, which herein is described as isomeric structure. Amorphous carbon nanodots are uniformly dispersed in the crystalline Li1.1V0.9O2 matrix in the core. In the shell however, Li1.1V0.9O2 nanoparticles are embedded in an amorphous carbon network. The Li1.1V0.9O2/C microspheres are tested as active material for anodes in lithium‐ion batteries, and exhibit an excellent reversible capacity of 295 mAh g−1, high capacity retention of 98 % after 100 cycles at 0.2 C and 95 % after 500 cycles at 2 C rate, and deliver wonderful rate capability of 250 mAh g−1 at 5 C. Thus, the Li1.1V0.9O2/C microspheres with isomeric core‐shell structure are promising candidates as anode material for commercial lithium‐ion batteries. In a nutshell: Li1.1V0.9O2/C microspheres are synthesized as anode material for lithium‐ion batteries. The Li1.1V0.9O2/C microspheres display identical composition but distinct texture of cores and shells, which herein is described as isomeric structure. As anodes in lithium‐ion batteries, the microspheres exhibit excellent overall electrochemical performance, rendering this material as promising candidate for the use in commercial lithium‐ion batteries. [ABSTRACT FROM AUTHOR]

Honeycomb-like nitrogen and sulfur dual-doped hierarchical porous biomass-derived carbon/sulfur composites (NSHPC/S) are successfully fabricated for high energy density lithium-sulfur batteries. The effects of nitrogen, sulfur dual-doping on the structures and properties of the NSHPC/S composites are investigated in detail by transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), and charge/discharge tests. The results show that N, S dual-doping not only introduces strong chemical adsorption and provides more active sites but also significantly enhances the electronic conductivity and hydrophilic properties of hierarchical porous biomass-derived carbon, thereby significantly enhancing the utilization of sulfur and immobilizing the notorious polysulfide shuttle effect. Especially, the as-synthesized NSHPC-7/S exhibits high initial discharge capacity of 1204 mA h g−1 at 1.0 C and large reversible capacity of 952 mA h g−1 after 300 cycles at 0.5 C with an ultralow capacity fading rate of 0.08 % per cycle even at high sulfur content (85 wt %) and high active material areal mass loading (2.8 mg cm−2) for the application of high energy density Li-S batteries. [ABSTRACT FROM AUTHOR]