Three‐dimensional nanostructured Co ₂ VO ₄ ‐decorated carbon nanotubes for sodium‐ion battery anode materials

Abstract

Abstract Since Co 2 VO 4 possesses a solid spinel structure and a high degree of stability, it has gained interest as a possible anode material for sodium‐ion batteries. However, the application of this electrode material is still hampered by its poor electrical conductivity and severe volume expansion. Uniform Co 2 VO 4 nanoparticles (CVO) were grown on carbon nanotubes (CNTs) by a simple solvothermal method to form string‐like conductive networks (CVO/CNTs). The flexible and highly conductive three‐dimensional (3D) carbon nanotubes and small‐sized CVO NPs can enhance the rapid transport of electrons, thereby enhancing the conductivity of the composite. String‐like conductive network structures have a larger specific surface area, enhancing electron/ion transmission by fully contacting the electrolyte. The findings demonstrate the superior Na + storing capability of the CVO/CNTs composite. The battery has a great rate performance (148.2 mAh·g −1 at 5 A·g −1 ) and outstanding long‐term cycling performance (147.3 mAh·g −1 after 1000 cycles at 1 A·g −1 ). In high‐rate, long‐cycle sodium‐ion batteries, CVO/CNTs composites offer a wide range of possible applications.