Carbon-enveloped pea-shaped vanadium nitride nanorods for aqueous zinc ion batteries

Abstract

Aqueous zinc ion batteries (AZIBs) have potential applications in grid-scale energy storage systems due to their cost-effectiveness and environmental friendliness. However, their performance is strongly influenced by the choice of cathode material. Herein, we propose a cathode material made of carbon-enveloped pea-shaped vanadium nitride nanorods (VNC). The pea-shaped nanorod structure has more active sites and shorter charge transfer paths, and the encapsulated carbon accelerates the VNC conductivity and effectively mitigates lattice collapse and dissolution of the vanadium-based material. Benefiting from the artificial core–shell structure, VNC delivers a high capacity of 630 mA h g⁻¹ at 0.1 A g⁻¹ and a desirable rate performance. A remarkable long cycling stability over 3000 cycles was observed with 83% capacity attenuation at 10 A g⁻¹. Meanwhile, VNC achieves a high energy density with 560.41 W h Kg⁻¹ at 89.19 W Kg⁻¹ power density and 327.28 W h Kg⁻¹ at 32 728.8 W Kg⁻¹ power density. Considering these observations, the uniqueness of VNC enunciates that it is an ideal electrode material, which validates the discovery of a brilliant pathway toward the large-scale development of high-performance vanadium-based cathodes for use in AZIBs.