Synthesis, Characterization, and Electrochemical Performance of Ce-Doped Ordered Macroporous Li3V2(PO4)3/C Cathode Materials for Lithium Ion Batteries

A series of Ce 3+ -doped ordered macroporous Li 3 V 2– x Ce x (PO 4 ) 3 /C ( x = 0, 0.01, 0.03, 0.05) samples have been fabricated via a colloidal crystal template method. The X-ray powder diffraction and scanning electron microscopy analysis demonstrate that the Ce element doping does not affect the original monoclinic structure and macroporous morphology of the pristine Li 3 V 2 (PO 4 ) 3 /C sample. Electrochemical measurement results prove that the Li 3 V 1.97 Ce 0.03 (PO 4 ) 3 /C sample presents the best electrochemical performance as the cathode material for lithium ion batteries among the as-prepared samples in the potential ranges of both 3–4.3 V and 3–4.8 V. The substitution of V 3+ with an appropriate amount of Ce 3+ increases the Li + diffusion coefficient based on the electrochemical impedance spectroscopy results, which is mainly responsible for the excellent electrochemical performance.