Hierarchically Porous V ₂ O ₃ Nanocomposite Confined within a Nitrogen-Doped Carbon Framework for High-Capacity Zinc-Ion Storage

The search for reliable high-capacitance cathodes for efficient Zn 2+ storage still faces challenges related to inherently poor conductivity and structural decay. Herein, porous V 2 O 3 embedded in N-doped carbon (V 2 O 3 –NC) microrods was prepared to achieve elevated electrical conductivity and structural integrity via in situ self-assembly and subsequent heat treatment. The robust connection of V 2 O 3 with the porous carbon structure significantly reduces the diffusion distance of Zn 2+ and accelerates charge transfer, leading to high reversible capacity and a long lifespan. Additionally, the existence of nitrogen regulates the electronic structure and introduces defects, generating more active sites. Consequently, V 2 O 3 –NC microrods present an impressive capacity of 357 mA h g –1 and maintain 120 mA h g –1 at a high-rate current density. Density functional theory (DFT) calculations further verify that V 2 O 3 –NC provides more Zn-ion reaction sites and diffusion pathways, facilitating rapid Zn 2+ diffusion. This strategy provides insight into constructing promising cathodes, enabling highly efficient Zn 2+ storage.