Phosphorus-doped TiO2-B nanowire arrays boosting robust pseudocapacitive properties for lithium storage

TiO2-B has received increasing interest as a possible anode for lithium-ion batteries, but its properties are restricted by the intrinsically low electronic conductivity. Herein, we first demonstrate that phosphorus doping can be an efficient approach to boost the pseudocapacitive properties of TiO2-B nanowire arrays. The phosphorus doping not only promotes electronic conductivity of TiO2-B nanowire arrays by modifying their electronic structure, but also significantly enhances the electrochemical surface reactivity. Density functional theory calculations further reveal that the phosphorus doping could improve the surface lithium affinity of TiO2-B nanowire arrays. Consequently the phosphorus-doped TiO2-B nanowire arrays simultaneously exhibit high reversible capacity (350.9 mAh g−1), remarkable rate capability (142.6 mAh g−1 at 30 C), and impressive cyclability (approximately 80% capacity retention efficiency over 3000 continuous cycles at 10 C), holding promise in high-energy and high-power lithium-ion batteries application.