Al-doped flower-like VO2(B) microspheres as high-performance cathode materials for lithium-ion batteries

Abstract

VO2(B), as a potential cathode material for lithium-ion batteries (LIBs), is attracting extensive attention from researchers because of its great superiority in terms of theoretical specific capacity, energy density, and cost. Nevertheless, VO2(B), leads to irreversible decay of specific capacity during cycling for reasons including structural stability and inferior electrical conductivity. In this work, the electrochemical performance of VO2(B) electrode materials are further enhanced via Al ion doping. The results reveal that the prepared Al-doped 3D flower-like VO2(B) microspheres exhibit a high initial discharge specific capacity (as high as 314.8 mAh/g at 0.1 A/g current density) at an Al doping amount of n(Al3+)/n(V5+) = 6.0 %. Moreover, it displays a first discharge specific capacity of up to 229.2 mAh/g at a current density of 1 A/g with the capacity retention rate of 90.0 % after 120 cycles. As a result, Al-doped 3D flower-like VO2(B) microspheres provide enormous commercialization potential as cathode materials for LIBs.