A cathode for Li-ion batteries made of vanadium oxide on vertically aligned carbon nanotube arrays/graphene foam.

Graphical abstract Highlights • Hierarchical porous V 2 O 5 /VA-CTNs is constructed for Li-ion battery cathode. • Incomplete coating of CNTs by V 2 O 5 exhibits superior charge transport properties. • The porous structure of V 2 O 5 coated with PEDOT ensures high ionic and electron conductivity. • The free-standing feature ensures high rate and cycle performance. Abstract A hierarchically structured free-standing V 2 O 5 /vertically aligned carbon nanotube/graphene foam (V 2 O 5 -VA-CNTs/GF) coated by PEDOT was designed. Instead of forming a thick coating layer around, the V 2 O 5 nanobelts disperse uniformly among the CNTs forest without severe aggregations. The PEDOT-V 2 O 5 -VA-CNTs/GF delivered a reversible capacity of 296.8 mAh g−1 at 1C, and has capacity retention of 113.3 mAh g−1 at 5C after 1000 cycles. First principles calculations indicate the addition of VA-CNTs to V 2 O 5 electrode could improve the electronic conductivity and facilitate Li-ion adsorption, which lead to the outstanding Li-ion storage and conversion behaviour. [ABSTRACT FROM AUTHOR]