Work

Rational Design of Carbon Covered V 2 O 3‐ x Decorated Amorphous MoO 2 Double‐Core–Shell Structure Facilitates Ultra‐High Stability and High‐Rate Performance in Lithium‐ion Batteries

Year: 2025

Type: article

Abstract: Amorphous materials, which bear unique atomic arrangements, have garnered significant study on lithium‐ion batteries due to inherent properties, including isotropy and defect distribution. Herein, a novel amorphous MoO 2‐ x @V 2 O 3‐ x @C double‐core–shell structure is ingeniously designed by simple solvothermal and pyrolytic reactions, and the valence states of amorphous MoO 2 and V 2 O 3 are precisely characterized using X‐ray absorption near‐edge structure spectroscopic measurements. In situ XRD, in situ EIS and density functional theory calculations confirm that the amorphous structure enhances the electronic conductivity of MoO 2‐ x @V 2 O 3‐ x @C‐2, optimizes the Li + relocation paths and the associated energy barriers, thus improving the Li + diffusion kinetics. Furthermore, the formation of V 2 O 3‐ x layer, along with the establishment of a 3D network structure of amorphous carbon, enhanced the electronic conductivity and mitigated swelling of the electrodes, thereby improving stability during battery cycling. Benefiting from this multiscale coordinated design, the optimized MoO 2‐ x @V 2 O 3‐ x @C electrodes exhibit high discharge capacity of 477.5 mAh g −1 at 10.0 A g −1 , along with exceptional cycling stability, showing minimal capacity loss even after undergoing 1000 cycles at 20.0 A g −1 . Additionally, MoO 2‐ x @V 2 O 3‐ x @C||LiCoO 2 full batteries maintain good capacity over 300 cycles. The proposed amorphous and core–shell structure fabrication concept offers novel insights into developing advanced high‐efficiency energy storage materials.

Source: Small

DOI: 10.1002/smll.202500441