V₂O₅ Nanowire Composite Paper as a High-Performance Lithium-Ion Battery Cathode

摘要

Ultralong, as long as ～1 mm, orthorhombic vanadium pentoxide (V_(2)O_(5)) nanowires were synthesized using a hydrothermal method. Free-standing and binder-free composite paper was prepared on a large scale by a two-step reduction method using free-standing V_(2)O_(5) nanowires as the skeleton and reduced graphene oxide (rGO) nanosheets as the additive. Such a free-standing V_(2)O_(5)/rGO composite paper as a cathode for lithium ion batteries possesses both structural integrity and extraordinary electrochemical performance. The reversible specific areal capacity of the V_(2)O_(5)/rGO composite paper electrode is 885 μAh/cm~(2) at 0.09 mA/cm~(2), much higher than that of the pure V_(2)O_(5) nanowire paper electrode (570 μAh/cm~(2)). It also shows excellent cycling performance at high rates with 30.9% loss of its initial capacities after 1000 cycles at a current rate of 0.9 mA/cm~(2). The excellent performance was attributed to the improved electronic conductivity and Li~(+) ion transport from the rGO addition.