The impact of the crystal structure and morphology on the electrochemical performance for CuFe2O4 in sodium ion batteries

摘要

The crystalline-controllable CuFe2O4 nanoparticles are successfully synthesized by a facile and scalable combustion method and investigated as anode materials for sodium ion batteries (SIBs). First-principles calculations are employed to confirm the phase transition temperature. The effects of reaction temperature on the phase composition, morphology and sodium storage properties of the products are innovatively investigated in detail. XRD data show that the phases of products varied from cubic to tetragonal types with the increased calcination temperature. The morphological results indicate that as the calcination temperature increases, the CuFe2O4 particle size gradually increases from nanoscale (similar to 25 nm) to submicron-scale (larger than 200 nm). The CuFe2O4 obtained at 150 degrees C exhibits superior electrochemical performance in the electrochemical tests. After 80 cycles, the discharge capacity remains 331.0 mA h g(-1), showing a high capacity retention (79.8%). The excellent electrochemical performance is mainly due to the cubic structure and nanoscale size, which can stabilize the material structure and offer a large activity area, facilitate Na ion diffusion and ease volume expansion.