CNTs boosting superior cycling stability of ZnFe2O4/C nanoparticles as high-capacity anode materials of Li-ion batteries

In recent years, bimetallic oxides have been widely researched as promising anode materials of Li-ion batteries due to their superior electrochemical capacities compared with single transition metal oxides. However, the low interior conductivity and volume change upon cycling result in poor cycling stability. Here, carbon nanotubes (CNTs) have been employed in a solvothermal method to successfully boost the high capacity and superior cycling stability of ZnFe2O4/C nanoparticles. The effect of CNTs content on the structure, morphology, and electrochemical property of the composite has been investigated. At 200 mA g–1, ZnFe2O4/C/CNTs composite shows a high first discharge specific capacity of 1375.7 mAh g–1. After 100 cycles, the specific capacity can be still maintained at 1430.4 mAh g–1. The excellent electrochemical performance of ZnFe2O4/C/CNTs is attributed to the protective shell of carbon coating layer and three-dimensional channel constructed by high-conductive CNTs, which can alleviate volume change upon cycling and accelerate the transfer of electrons and lithium ions. This work provides a feasible idea for improving the properties of carbon-modified bimetallic oxide anode materials of secondary rechargeable batteries.