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The practical application of lithium–sulfur batteries is still limited by the lithium polysulfides (LiPSs) shuttling effect on the S cathode and uncontrollable Li‐dendrite growth on the Li anode. Herein, elaborately designed WSe2 flakelets immobilized on N‐doped graphene (WSe2/NG) with abundant active sites are employed to be a dual‐functional host for satisfying both the S cathode and Li anode synchronously. On the S cathode, the WSe2/NG with a strong interaction towards LiPSs can act as a redox accelerator to promote the bidirectional conversion of LiPSs. On the Li anode, the WSe2/NG with excellent lithiophilic features can regulate the uniform Li plating/stripping to mitigate the growth of Li dendrite. Taking advantage of these merits, the assembled Li−S full batteries exhibit remarkable rate performance and stable cycling stability even at a higher sulfur loading of 10.5 mg cm−2 with a negative to positive electrode capacity (N/P) ratio of 1.4 : 1. [ABSTRACT FROM AUTHOR]

Use of catalytic materials is regarded as the most desirable strategy to cope with sluggish kinetics of lithium polysulfides (LiPSs) transformation and severe shuttle effect in lithium–sulfur batteries (LSBs). Single‐atom catalysts (SACs) with 100 % atom‐utilization are advantagous in serving as anchoring and electrocatalytic centers for LiPSs. Herein, a novel kind of tungsten (W) SAC immobilized on nitrogen‐doped graphene (W/NG) with a unique W‐O2N2‐C coordination configuration and a high W loading of 8.6 wt % is proposed by a self‐template and self‐reduction strategy. The local coordination environment of W atom endows the W/NG with elevated LiPSs adsorption ability and catalytic activity. LSBs equipped with W/NG modified separator manifest greatly improved electrochemical performances with high cycling stability over 1000 cycles and ultrahigh rate capability. It indicates high areal capacity of 6.24 mAh cm−2 with robust cycling life at a high sulfur mass loading of 8.3 mg cm−2. [ABSTRACT FROM AUTHOR]

Main observation and conclusion: There is no doubt that SiOx and carbon composite is one of the promising anode materials for lithium‐ion batteries owing to its high capacity and rational cycling stability. Herein, we report a sol‐gel synthesis followed by molten salt carbonization route to fabricate graphene‐like carbon nanosheet wrapped SiOx/C submicrospheres (SiOx/C@2D‐C). The in‐situ generated carbon nanosheets under molten salt condition can further improve the electroconductivity, restrain the volumetric expansion and guarantee the structural integrity of the electrode. As a result, the as‐obtained SiOx/C@2D‐C delivers a discharge capacity of 559 mAh·g−1 at 0.5 A·g−1 after 200 cycles and 548 mAh·g–1 at 1.0 A·g−1 even after 1000 cycles. The full cell assembled with SiOx/C@2D‐C as anode and commercial LiFePO4 as cathode can achieve an energy density of 200 Wh·kg−1 and maintain a capacity of 66.7% after 100 cycles with a working potential of 2.8 V. The approach is simple and cost effective, which is promising for mass production of SiOx‐based materials for high energy LIBs. [ABSTRACT FROM AUTHOR]

Hybrid hierarchical micro/nanostructures possess great potential in engineering of advanced electrode materials for sodium‐ion batteries (SIBs). Herein, a sandwich hierarchical architecture composed of ZnSe nanoparticles fastened in N‐doped carbon polyhedra anchoring onto graphene with the modification of MoSe2 nanosheets (ZnSe⊂N‐C@MoSe2/rGO) is synthesized by a self‐template and subsequent selenization strategy. Due to the distinctive architectural and multicompositional features, these hybrids deliver a high reversible capacity of 319.4 mAh g−1 at 1 A g−1 for 1800 cycles, 206.5 mA h g−1 at 6 A g−1 for 2800 cycles, and 177.7 mAh g−1 at 10 A g−1 for 5000 cycles, as well as a better rate capability up to 10 A g−1 with a reversible capacity of 224.4 mAh g−1 as an anode material for SIBs. By comparing the capacity contribution, electrochemical impedance spectra and DNa+ of different materials, the advantages of ZnSe⊂N‐C@MoSe2/rGO are confirmed. The sodium storage mechanism of hybrids is further revealed by in situ X‐ray diffraction patterns and high‐resolution transmission electron microscopy results. The improved sodium storage properties of hybrids manifest the significance of elaborate construction of novel multicomponent hierarchical architectures with higher complexity. [ABSTRACT FROM AUTHOR]

Lithium–sulfur batteries are deemed to be one of the most promising energy storage alternatives due to the high theoretical capacity and cost‐effectiveness. The significant challenge in exploring novel sulfur host materials is to simultaneously inhibit the shuttle effect and heighten the reaction kinetics. Herein, a novel hybrid host consisting of W2C atomic nanoclusters (NCs) grown on a N/P‐codoped graphene framework (W2C@N/P‐rGO) is designed and fabricated for the first use in lithium–sulfur batteries. By means of first‐principle calculations and the kinetics analysis including lithium ion diffusion coefficient and charge transfer resistance, the introduction of W2C atomic NCs benefits the enhancement of electrochemical kinetics on a polar hybrid conductor. Furthermore, the intense ability of chemically sequestrating the soluble polysulfides by W2C atomic NCs ensures the high utilization of sulfur, making the high capacity retention. With a high sulfur loading of 3.1 mg cm−2, the W2C@N/P‐rGO/sulfur composite cathode indicates a significantly enhanced electrochemical performance. This work may open up a new avenue to design novel host candidates for advanced lithium–sulfur batteries. [ABSTRACT FROM AUTHOR]

Main observation and conclusion: There is no doubt that SiOx and carbon composite is one of the promising anode materials for lithium‐ion batteries owing to its high capacity and rational cycling stability. Herein, we report a sol‐gel synthesis followed by molten salt carbonization route to fabricate graphene‐like carbon nanosheet wrapped SiOx/C submicrospheres (SiOx/C@2D‐C). The in‐situ generated carbon nanosheets under molten salt condition can further improve the electroconductivity, restrain the volumetric expansion and guarantee the structural integrity of the electrode. As a result, the as‐obtained SiOx/C@2D‐C delivers a discharge capacity of 559 mAh·g−1 at 0.5 A·g−1 after 200 cycles and 548 mAh·g–1 at 1.0 A·g−1 even after 1000 cycles. The full cell assembled with SiOx/C@2D‐C as anode and commercial LiFePO4 as cathode can achieve an energy density of 200 Wh·kg−1 and maintain a capacity of 66.7% after 100 cycles with a working potential of 2.8 V. The approach is simple and cost effective, which is promising for mass production of SiOx‐based materials for high energy LIBs. [ABSTRACT FROM AUTHOR]