Al-doping endows V2O5·4VO2 enhanced lithium storage

Vanadium oxides, being a potential cathode material for lithium ion batteries (LIBs), are extensively interested from scientists owing to their greater advantages in terms of theoretical specific capacity, energy density, and cost. However, the specific capacity of vanadium oxides decays irreversibly during cycling process for reasons including its structural stability and poor electrical conductivity. As a consequence, the electrochemical performance of V2O5·4VO2 electrode materials，in this paper, is further enhanced via metal ion doping. Herein, Al-doped 3D flower-like V2O5·4VO2 microspheres are successfully prepared via a green and simple hydrothermal synthesis with Al(NO3)3·9H2O as the aluminum source. It is revealed that when the Al doping amount is n(Al3+)/n(V5+)=5.00%, the prepared 3D flower-like V2O5·4VO2 microsphere exhibits high specific capacity (the specific capacity is up to 385.1 mAh/g at a current density of 0.1 A/g), outstanding rate performance (presenting a high capacity of 264.1 mAh/g at 1 A/g current density), and excellent cycling stability (90.7% capacity retention after 120 cycles at 1 A/g current density). As a result, Al-doped 3D flower-like V2O5·4VO2 microspheres hold enormous commercialization potential as cathode materials for LIBs.