One-step fabricating nitrogen-doped TiO₂ nanoparticles coated with carbon to achieve excellent high-rate lithium storage performance

Nitrogen-doped TiO₂ nanoparticles coated with N-doped carbon are prepared by simply hydrolyzing tetrabutyl titanate to obtain TiO₂ nanoparticles followed by heating the mixture of nanoparticles and urea at 550 °C for 5 h. The combination of simultaneously N-doping with coating carbon results in the enhancement in electronic and ionic conductivities, thus the modified TiO₂ exhibits outstanding reversible capacities of 227.7, 204.0, 186.4, 160.6, 113.1 mAh g⁻¹ corresponding to current densities of 100, 200, 400, 800 and 1600 mA g⁻¹. In particular, the modified TiO₂ could deliver an excellent long-term cycling capacity of 106.4 mAh g⁻¹ even cycled 2500 times at a high density of 500 mA g⁻¹ with an average capacity loss of only 0.016% per cycle. The modified TiO₂ fabricated by this simple and economical method could serve as the anode material for lithium-ion batteries with high power-density.