Influence of reduction treatment for TiNb2O7 nanoparticles on the electrochemical properties for Li-ion batteries
Journal
Journal of the American Ceramic Society
ISSN
0002-7820
1551-2916
Date Issued
2024-10-31
Author(s)
DOI
10.1111/jace.20201
Abstract
The discharge capacities and rate capability of TiNb2O7 powders were enhanced through the additional postreduction treatment. X-ray photoelectron spectroscopy and electron paramagnetic resonance results confirmed the formation of oxygen vacancies in TiNb2O7 powders after a reduction treatment. The appearance of oxygen vacancies in TiNb2O7 powders formed the impurity level in the forbidden gap and decreased the bandgap values of TiNb2O7. Compared with the pristine TiNb2O7 powders, when TiNb2O7 powders were reduced at 400°C for 40 min, the charge transfer resistance of prepared samples was reduced from 43.67 to 19.35 Ω, and the pseudocapacitive contribution of TiNb2O7 was increased from 44% to 59%. In addition, the discharge capacities at 0.1 and 20 C of prepared batteries were increased by 10.84% and 105.85%, respectively. On the other hand, increasing the temperature in the reduction treatment caused the formation of Ti4+/Ti3+ and Nb5+/Nb4+ pairs and decreased the amounts of available redox couples, thereby deteriorating the electrochemical performance of prepared batteries. The results in the present study revealed that the discharge capacities and rate capability of TiNb2O7 powders were enhanced through a postreduction treatment.
Subjects
a reduction treatment
electrochemical performance
EPR
TiNb2O7
XPS
SDGs
Publisher
Wiley
Type
journal article