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 at 1.0 C and large reversible capacity of 952 mA h g 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 ) for the application of high energy density Li-S batteries.

The polysulfide shuttle effect is one of the most important problems hindering the commercial application of lithium−sulfur batteries (LSBs). In order to solve the above problem and promote LSBs commercialization, herein a holistic design strategy on the molybdenum disulfide-coated nitrogen-doped mesoporous carbon sphere/sulfur (NMCS@MoS 2 /S) composite cathode and carbon nanotube/chitosan modified separator (CNT/CH) is proposed. In the holistic design, the NMCS@MoS 2 plays a role in the host of sulfur and the lithium polysulfides (LiPSs) adsorbent; the CNT/CH modified separator also has an inestimable role in promoting lithium ion transport and chemical adsorption of LiPSs. The results show that the LSBs with the NMCS@MoS 2 /S-CNT/CH release a high reversible capacity of 827 mAh g −1 with a high capacity retention of 92.4% at 0.5 C after 200 cycles. The delicate design exhibits apparently excellent electrochemical performance and provides an exciting strategy for solving the shuttle effect of LiPSs and boosting industrialization of LSBs.

The commercialization of lithium‐sulfur (Li‐S) batteries is greatly hindered due to serious capacity fading caused by the polysulfide shuttling effect. Optimizing the structural configuration, enhancing reaction kinetics of the sulfur cathode, and increasing areal sulfur loading are of great significance for promoting the commercial applications of Li‐S batteries. Herein, the multifunctional polysulfide scavengers based on nitrogen, sulfur co‐doped carbon cloth (DCC), which is supported by flower‐like MoS2 (1T‐2H) decorated with BaMn0.9Mg0.1O3 perovskite particle (PrNP) and carbon nanotubes (CNTs), namely, DCC@MoS2/PrNP/CNTs, are delicately designed and synthesized. The physical confinement, chemical coupling, and catalysis conversion for active sulfur are achieved simultaneously in this polysulfide motif. Due to these merits, the as‐fabricated self‐supported DCC@MoS2/PrNP/CNTs/S manifests an excellent reversible areal capacity of 4.75 mAh cm−2 with an ultrahigh sulfur loading of 5.2 mg cm−2 at the 50th cycle. The outstanding cycling stability is obtained upon 800 cycles with a large reversible capacity of 871 mAh g−1 and a negligible fading rate of 0.02% per cycle at a rate of 1.0 C, suggesting its promising prospects for the commercial success of high‐performance Li‐S batteries toward flexible electronic devices and energy storage equipment.

In order to restrict the polysulfide shuttle effect and enhance sulfur utilization of lithium–sulfur batteries (LSBs) especially at low charge/discharge rates, a facile hydrothermal synthesis and subsequent heating melting treatment are used to synthesize the heteroatom-doped carbon nanotubes/sulfur composite cathode. The composition analysis and structure characteristics of samples are examined by X-ray photoelectron spectroscopy, X-ray powder diffraction, and transmission electron microscopy. The electrochemical performances of samples are measured by cyclic voltammetry and charge/discharge experiments. The results show that N, B, S tridoped active carbon nanotubes (ACNTs) with abundant mesoporous structure enable fast Li+ transmittal and provide strong polysulfide adsorption ability. More importantly, they offer enough mechanical strength to support high sulfur loading (77 wt %) that maximizes their chemical role and can accommodate large volume changes. The N, B, S tridoped ACNTs/S composite exhibits a superb incipient capacity of 1166 mAh/g-S at 0.3 C and large reversible capacity of 881 mAh/g-S at the 700th cycle. To further promote the cyclic lifespan of LSB, the as-prepared N, B, S tridoped ACNTs acted as both sulfur matrix and spring functional layer and achieved a large reversible specific capacity of about 713 mAh/g-S at the 1400th cycle at lofty current density of 0.5 C with a slow capacity decay of 0.014% 1/cycle and a higher sulfur loading of 90 wt %. Accordingly, reasonable design for the heteroatom doping element in carbon material and separator modification will be distinctly vital for enhancing the electrochemical performance of the LSB and boosting its industrial application.

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