Synthesis and characterization of Fe-doped vanadium oxide nanorods and their electrochemical performance

Fe-doped vanadium oxide nanorods were synthesized by a simple hydrothermal method. Experimental results demonstrate that doping moderate amount of metal ions can inhibit the breakage of the morphology structure during phase transition and enhance the structure stability of vanadium oxide nanorods after calcination. Meanwhile, metal ions can enhance the electrical conductivity of electrodes and ion diffusion coefficient, but doping more metal ions can reduce ion diffusion coefficient due to ions block Li+ diffusion path. The unbroken Fe-doped vanadium oxide nanorods play an important role in improving the electrochemical performance of electrodes. Fe-doped nanorods (0.15Fe-V2O5) can deliver a high initial capacity of 271 mA h g−1, and a good capacity retention of 82.2% at a current density of 1 A g−1 after 50 cycles, while un-doped V2O5 electrode materials show a low capacity retention of ∼65.6% under the same condition. Improved performance of Fe-doped vanadium oxides is mainly attributed to the enhancement of electrical conductivity and the maintenance of nanorods structure during electrochemical cycling.