Enhanced High-Rate Capability of the C-N-Doped TiO2 as Anode Material for Lithium-Ion Battery

Abstract

The surface-modified TiO2 with interstitial carbon and nitrogen atoms doping is successfully synthesized through calcining polyaniline/TiO2 nanocomposite in air. The C-N-doped TiO2 as anode exhibits a large initial discharge capacity of 202.5 mAh g−1. In particular at the large current density of 1000 mA g−1, the discharge capacity can be stably maintained at 156.7 mAh g−1 after 150 cycles. The electrochemical impedance spectroscopy (EIS) demonstrates that the C-N doped TiO2 has a lower charge-transfer resistance, due to that the interstitial carbon and nitrogen atoms narrow the band gap of TiO2.