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Layered VS2has high theoretical capacity and is considered a promising anode material for lithium-ion batteries. However, its poor cycle stability seriously affects its commercial application. The smart design of anode material microstructure is a crucial point to optimize the stability of batteries. Herein, a hierarchical composite of VS2/CNTs/C was successfully fabricated via a simple one-step solvothermal method, in which few-layer VS2nanosheets were in situ self-assembled on a 3D CNTs cross-linked network skeleton and coated with a thin carbon layer. The interlayer spacing of (001) planes of VS2nanosheets was expanded from 0.58 nm to 0.89 nm due to NH4+intercalation during the solvothermal reaction. Density functional theory (DFT) calculations demonstrated that expanded interlayer spacing of VS2can enhance the electron conductivity and significantly reduce the diffusion barrier of Li+. More importantly, the 3D CNTs skeleton could prevent the aggregation of VS2nanosheets, provide a fast ionic/electronic migration channel, and ensure a large specific surface area and an extra buffer space. In addition, the carbon coating could further increase the conductivity and stabilize the connection between the VS2nanosheets and CNTs skeleton. Benefiting from their synergistic effects, the VS2/CNTs/C electrode exhibited an enormous Li+diffusion coefficient and favorable capacitive kinetics, and delivered excellent lithium storage performance, such as a large reversible specific capacity of 1075 mAh g−1at 0.1 A g−1, a high rate performance of 592 mAh g−1at 2 A g−1, and a remarkable cycling stability with a specific capacity of 629 mAh g−1after 900 cycles at 1 A g−1. This work may guide the design of other similar anode materials and help to understand their energy storage mechanism.

The mixture of the rare-earth CeO2and ZrO2particulates was used for fabricating the hybridized AZ31BMg/(CeO2+ZrO2)pcomposites by utilizing friction stir processing with a multiple-tool pass strategy. The structure, mechanical properties (tensile strength and hardness), tribological performances (wear properties) and corrosion behaviours of the hybrid composites were examined. The findings reveal the elimination of tunnel-like defects and clustering of the CeO2+ZrO2particles in the composite after the multiple passes of the tool due to the successive mechanical stirring-assisted material flow. The rise in the tool passes reduced the mean grain sizes (7.91-3.02 μm), the particle sizes (5.47 - 2.28 μm), the average friction coefficient (0.45 - 0.18) and the specific wear rate (4.26 × 10−5- 2.17 × 10−5mm3/Nm) of the composite. The tensile strength (172 - 239 MPa), and the corrosion performance of the hybrid composite were also improved via the multiple tool pass strategy. Multiple tool pass is thus recommended for the fabrication of Mg-based hybrid composites.