화학공학소재연구정보센터
Thin Solid Films, Vol.596, 29-33, 2015
Titanium oxynitride thin films as high-capacity and high-rate anode materials for lithium-ion batteries
Titanium oxynitride (TiOxNy) was synthesized by reactive magnetron sputtering in a mixed N-2/O-2/Ar gas at ambient temperature. TiOxNy thin films with various amounts of nitrogen contents were deposited by varying the N-2/O-2 ratios in the background gas. The synthesized TiOxNy films with different compositions (TiO1.837N0.060, TiO1.890N0.068, TiO1.865N0.073, and TiO1.882N0.163) all displayed anatase phase, except TiO1.882N0.163. The impedances and grain sizes showed obvious variations with the nitrogen contents. A wide potential window from 3.0 V to 0.05 V, high-rate charge-discharge testing, and long cycle testing were applied to investigate the performances of synthesized TiOxNy and pure TiO2 as anodes for lithium-ion batteries. These TiOxNy anodes can be cycled under high rates of 125 mu A/cm(2) (10 degrees C) because of the lower charge-transfer resistance compared with the TiO2 anode. At 10 degrees C the discharge capacity of the optimal TiOxNy composition is 1.5 times higher than that of pure TiO2. An unexpectedly large reversible capacity of similar to 300 mu Ah/cm(2) mu m (similar to 800 mAh/g) between 1.0 V and 0.05 V was recorded for the TiOxNy anodes. The TiOxNy anode was cycled (3.0 V to 0.05 V) at 10 degrees C over 300 times without capacity fading while delivering a capacity of similar to 150 mu Ah/cm(2) mu m (similar to 400 mAh/g). (C) 2015 Elsevier B.V. All rights reserved.