In situ sol–gel synthesis of Ti <sub>2</sub> Nb <sub>10</sub> O <sub>29</sub> /C nanoparticles with enhanced pseudocapacitive contribution for a high‐rate lithium‐ion battery
Guangyin Liu, Yiyang Zhao, Yufeng Tang, Xiaodi Liu, Miao Liu, Peng-Jiang Wu
Abstract
Abstract Ti 2 Nb 10 O 29 /C nanoparticles with a carbon content of 13 wt% and a mean size of 50 nm were fabricated through a convenient and effective in situ sol–gel process. The small grain size and carbon modification can improve the pseudocapacitive effect of the Ti 2 Nb 10 O 29 /C nanoparticles, leading to excellent rate capacity, especially at high current rate. Specifically, the discharge capacity of the Ti 2 Nb 10 O 29 /C electrode is 258.3, 236.0, 216.6, 184.5 and 161.5 mAh·g −1 at different current densities of 1C, 5C, 10C, 20C and 30C. Nevertheless, the discharge capacity of the Ti 2 Nb 10 O 29 electrode is 244.9 mAh·g −1 at 1C, which is rapidly reduced to 89.7 mAh·g −1 at 30C. In addition, the small size and carbon layer of the Ti 2 Nb 10 O 29 /C nanoparticles can supply abundant active sites for Li + storage as well as enhance the electronic conductivity and Li + diffusion, endowing these nanoparticles with a high discharge capacity and excellent cycle performance.