Facile synthesis of multiwalled carbon nanotube–V2O5 nanocomposites as cathode materials for Li-ion batteries

Abstract

Multiwalled carbon nanotube (MWCNT)–vanadium pentoxide (V2O5) nanocomposites have been fabricated using a facile and environmental friendly hydrothermal method without any pretreatment, surfactants, or chelate agents added. The as-annealed nanocomposites are characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM), and the results indicate that V2O5 nanoparticles grew on MWCNTs. As a cathode material for lithium batteries, it exhibits superior electrochemical performance compare to the pure V2O5 powders. A high specific discharge capacity of 253 mA h g−1 can be obtained for the 15 % MWCNT–V2O5 nanocomposite electrodes, which retains 209 mA h g−1 after 50 cycles. However, the pure V2O5 powder electrodes only possess a specific discharge capacity of 157 mA h g−1 with a capacity retention of 127 mA h g−1 after 50 cycles. Moreover, the MWCNT–V2O5 nanocomposite electrodes show an excellent rate capability with a specific discharge capacity of 180 mA h g−1 at the current rate of 4 C. The enhanced electrochemical performance of the nanocomposites is attributed to the formation of conductive networks by MWCNTs, and large surface areas of V2O5 nanoparticles grew on MWCNTs which stabilizes these nanoparticles against agglomeration.