High lithium electroactivity of boron-doped hierarchical rutile submicrosphere TiO2

Abstract

We have reported a facile method to fabricate hierarchical boron-doped rutile submicrosphere TiO₂ (SMT), whose primary particles are ∼20 nm in diameter. The as-synthesized boron-doped SMT shows excellent cycling performance and rate capability in comparison with undoped TiO₂ as an anode material in Lithium-Ion Batteries (LIBs). It has a very stable capacity of ∼190 mA h g⁻¹ for 500 cycles at 1C. In addition, the density functional theory (DFT) calculations are carried out to indicate that a low concentration (<1.0 at%) of boron doping could enhance the carrier mobility μ and electrical conductivity σ, and thus reveal the relationship between the electronic structure of boron-doped SMT and the performances of the boron-doped SMT anode in LIBs. Our results also clearly demonstrate the importance and advantage of the hierarchical submicrometer-sized spherical morphology of the TiO₂ anode in LIBs.