Ammonia‐Annealed TiO₂ as a Negative Electrode Material in Li‐Ion Batteries: N Doping or Oxygen Deficiency?

Abstract

Improving the chemical diffusion of Li ions in anatase TiO2 is essential to enhance its rate capability as a negative electrode for Li-ion batteries. Ammonia annealing has been used to improve the rate capability of Li4 Ti5 O12 . Similarly, ammonia annealing improves the Li-ion storage performance of anatase TiO2 in terms of the stability upon cycling and the C-rate capability. In order to distinguish whether N doping or oxygen deficiencies, both introduced upon ammonia annealing, are more relevant for the observed improvement, a systematic electrochemical study was performed. The results suggest that the creation of oxygen vacancies upon ammonia annealing is the main reason for the improvement of the stability and C-rate capability.

Copper‐Doped Dual Phase Li4Ti5O12–TiO2 Nanosheets as High‐Rate and Long Cycle Life Anodes for High‐Power Lithium‐Ion Batteries

“…[33] Increasing the amount of Cu results in increased electron mobility, but it decreases Li-ion mobility. [34] If the addition amount is below 0.05, the enhancement in the electrical conductivity out-weighs the reduction in ion mobility, and therefore, excellent electrochemical performance is exhibited. At a certain point, ion mobility starts to outweigh electron mobility, and the performance begins to decay; this corresponds to LTO + 0.1 Cu and LTO + 0.15 Cu.…”

Effect of the specific surface area on thermodynamic and kinetic properties of nanoparticle anatase TiO2 in lithium-ion batteries

“…However, it leads to a lower specific energy of the battery. The main drawback of titania materials, which is limiting its electrochemical performance, is the low electrical conductivity, which has been addressed by using carbon additives [4,5] or doping [6,7].…”

CNT-TiO2−δ Composites for Improved Co-Catalyst Dispersion and Stabilized Photocatalytic Hydrogen Production

“…In the CNT-TiO2−δ composites, the covering of TiO2 by CNTs leads to an additional loss of accessible surface area. XRD patterns shown in Figure 2 revealed that the pure anatase phase is present in oxygen-deficient TiO2−δ and all of the CNT-TiO2−δ composites [24]. Clear CNT diffraction peaks were not observed in any of the CNT-TiO2−δ composites, probably due to the insufficiently crystalline structure of the CNTs synthesized at relatively low temperature.…”