Electrochemical elucidation of Co_0.5M_0.5V₂O₄(M = Fe or Zn) nanocomposite anode materials for Li-ion storage

This work proposes spinel Co0.5M0.5V2O4 (M = Fe or Zn) nanocomposites as novel anode materials for Li-ion storage. Their electronic properties are predicted through theoretical analysis. The equal ratio of binary metal mixed V-O matrix spinel compounds actively improved the cyclic and rate capacities. The Co0.5Zn0.5V2O4 (CZVO) composite exhibits higher cyclic and rate capacities than the bare CoV2O4 (CVO) and Co0.5Fe0.5V2O4 (CFVO) samples. The CZVO sample demonstrates a higher reversible discharge capacity of 434 mA h g-1 over 100 cycles at a current density of 200 mA g-1. However, it has showed a higher rate capacity (129 mA h g-1 at 5 A g-1) than the other prepared samples (40 mA h g-1 for bare CVO and 99 mA h g-1 for CFVO at 5 A g-1). The CZVO sample delivers superior electrochemical performance due to the conductivity improvements and a high order of the Co2+/Co3+ oxidation ratio. Thus, this report offers potential anode materials as an approach to improve binary metal mixed oxides for high-performance lithium storage applications in future.