Sodium (Na) metal anode possesses abundant resource and high theoretical capacity, but is still limited by severe Na dendritic growth and thus resulting in poor cycle/safety problems. To facilitate homogeneous Na deposition during repeated stripping/plating processes, we herein report the microwave hydrothermal synthesis of Sb2S3 nanorod hierarchies and demonstrate the first use of Sb2S3 as a substrate to in situ construct “sodiophilic” nucleation sites, which efficiently promote the uniform dendrite-free Na deposition/growth. The Na-predeposited Sb2S3 (Na/Sb2S3) anode displays a low voltage hysteresis (28.5 mV at 5 mA cm–2), a superior cyclic performance (3000 cycles), and a rate capability (10 mA cm–2) with highly decreased interfacial resistance. Moreover, the Na-ion full cell assembled by the Na/Sb2S3 anode and the Na3V2(PO4)3 cathode exhibits much enhanced sodium storage performances with small voltage polarizations, as compared with the bare Na-based full batteries.

Building 3D electron-conducting scaffolds has been proven to be an effective way to alleviate severe dendritic growth and infinite volume change of sodium (Na) metal anodes. However, the electroplated Na metal cannot completely fill these scaffolds, especially at high current densities. Herein, we revealed that the uniform Na plating on 3D scaffolds is strongly related with the surface Na+ conductivity. As a proof of concept, we synthesized NiF2 hollow nanobowls grown on nickel foam (NiF2@NF) to realize homogeneous Na plating on the 3D scaffold. The NiF2 can be electrochemically converted to a NaF-enriched SEI layer, which significantly reduces the diffusion barrier for Na+ ions. The NaF-enriched SEI layer generated along the Ni backbones creates 3D interconnected ion-conducting pathways and allows for the rapid Na+ transfer throughout the entire 3D scaffold to enable densely filled and dendrite-free Na metal anodes. As a result, symmetric cells composed of identical Na/NiF2@NF electrodes show durable cycle life with an exceedingly stable voltage profile and small hysteresis, particularly at a high current density of 10 mA cm–2 or a large areal capacity of 10 mAh cm–2. Moreover, the full cell assembled with a Na3V2(PO4)3 cathode exhibits a superior capacity retention of 97.8% at a high current of 5C after 300 cycles.

Titanium dioxide (TiO2) has been considered as a promising anode material for sodium‐ion batteries (SIBs), because of its abundance, safety and eco‐friendliness. However, the inferior electronic conductivity and low sodium ion diffusion rate of TiO2 hinder its improvement of electrochemical performance. To overcome these drawbacks, herein, core‐shell Se‐doped TiO2@carbon nanotubes (denoted as Se‐TiO2@CNTs) are successfully designed and fabricated, in which the TiO2 nanoparticle aggregated shells are conformally coated on the carbon nanotubes, while the metallic Se species are physically confined within the meso/micropores. When examined as a SIB anode, the Se‐TiO2@CNTs electrode demonstrates excellent sodium storage performance, correspondingly delivering high reversible capacities of 222.7/208.5 mA h g−1 after 200/1000 cycles at current densities of 0.2/1.0 A g−1, and even a capacity of 140.2 mA h g−1 after 4500 cycles at a high‐rate of 5.0 A g−1. The high reversible capacity, long‐term cycling stability, and high‐rate capability of the Se‐TiO2@CNTs can be owing to the unique structure characteristics, as the hollow/porous structure with high specific surface area of 335.4 m2 g−1 efficiently shortens the Na+ diffusion length and facilitates the electrolyte penetration, while Se‐doping and carbon supporting greatly enhance the electronic conductivity of the Se‐TiO2@CNTs electrode.

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By virtue of complexing Ni/Co/Mn ions with glucose under solvothermal condition, well-defined spherical Ni/Co/Mn-gluconate with tunable sizes and elements are prepared and readily converted into yolk-shelled Li(NixCoyMn1-x-y)O2. As an example,...