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The 0D C60 simultaneously improves the ionic conductivity of PEO, suppresses lithium dendrite penetration, and inhibits polysulfide shuttle.

In the present study, a facile strategy to construct 3D vanadium nitride (VN)-decorated lotus root-like N-doping carbon nanofibers (VN-NCNFs) as current collector with stable electrochemical performance for Li-S batteries was described. The polar conductive VN with catalytic property provides chemical adsorption to trap lithium polysulfides (LiPSs) and enhances the transformation of LiPSs. The Li-S batteries with as-prepared VN-NCNFs current collector display stable cycling performance with a capacity of 700 mAh g−1 after 500 cycles at 0.2 C.

The commercial course of Li-S batteries (LSBs) is impeded by several severe problems, such as low electrical conductivity of S, Li2 S2 , and Li2 S, considerable volume variation up to 80% during multiphase transformation and severe intermediation lithium polysulfides (LiPSs) shuttle effect. To solve above problems, conductive FeOOH interlayer is designed as an effective trapper and catalyst to accelerate the conversion of LiPSs in LSBs. FeOOH nanorod is effectively affinitive to S that Fe atoms act as Lewis acid sites to capture LiPSs via strong chemical anchoring capability and dispersion interaction. The excellent electrocatalytic effect enables that reduced charging potential barrier and enhanced electron/ion transport is realized on the FeOOH interlayer to promote LiPSs conversion. Significantly, Li2 S oxidation process is improved on the FeOOH interlayer determined as a combination of reduced Li2 S decomposition energy barrier and enhanced Li-ion transport. Therefore, the multifunctional FeOOH interlayer with conductive and catalytic features show strong chemisorption with LiPSs and accelerated LiPSs redox kinetics. As a result, LSBs with FeOOH interlayer displays high discharge capacity of 1449 mAh g-1 at 0.05 C and low capacity decay of 0.05% per cycle at 1 C, as well as excellent rate capability (449 mAh g-1 at 2 C).

Germanium is considered as a potential anode material for sodium-ion batteries due to its fascinating theoretical specific capacity. However, its poor cyclability resulted from the sluggish kinetics and large volume change during repeated charge/discharge poses major threats for its further development. One solution is using its ternary compound as an alternative to improve the cycling stability. Here, high-purity CuGeO3 nanowires were prepared via a facile hydrothermal method, and their sodium storage performances were firstly explored. The as-obtained CuGeO3 delivered an initial charge capacity of 306.7 mAh g−1 along with favorable cycling performance, displaying great promise as a potential anode material for sodium ion batteries.

In this study, ternary Cu2SnS3 (CTS) nanostructure materials with high crystallinity were successfully prepared via a facile solvothermal method, which was followed by high-temperature treatment. The morphology of the as-synthesized samples is uniform flower-like spheres, with these spheres consisting of hierarchical nanosheets and possessing network features. Sodium storage measurements demonstrate that the annealed CTS electrodes have high initial reversible capacity (447.7 mAh&middot, g&minus, 1 at a current density of 100 mA&middot, 1), good capacity retention (200.6 mAh&middot, 1 after 50 cycles at a current density of 100 mA&middot, 1) and considerable rate capability because of their high crystallinity and unique morphology. Such good performances indicate that the high crystallinity CTS is a promising anode material for sodium ion batteries.