The template-free synthesis of hierarchically porous anatase TiO2via acid-etching for enhancing the cycling stability and reversible capacity of lithium ion batteries

• Main Authors: Wang, Xiaobing, Jia, Zhichao, Liu, Fuyuan, Liang, Huijun, You, Xinxin, Wang, Kui, Lou, Xiangdong, Shuang, Wei, Xiao, Lichun, Cai, Bibo, Yang, Lin
• Format: Journal Article
• Published: 18.05.2016
• ISSN: 2046-2069
• DOI: 10.1039/c6ra03821b

Although anatase TiO 2 demonstrates good performance in many applications, it is very difficult to synthesize nanocrystalline anatase TiO 2 with high specific surface areas. Herein, two-dimensional hierarchically porous anatase TiO 2 with specific surface area of 486 m 2 g −1 , is fabricated through acetic acid etching, which facilitates the crystal phase transition of amorphous TiO 2 . The pore sizes are within the ranges of 2-6 nm and 15-80 nm, and the pore diameters are 3.5 nm and 45 nm. As the anode materials for lithium ion batteries, the initial discharge capacity of hierarchically porous anatase TiO 2 reaches to 449 mA h g −1 at a current rate of 0.1 A g −1 and retains 191 mA h g −1 after 60 cycles. In particular, the discharge capacities of 42 and 35 mA h g −1 can be resumed after 750 cycles at the current rates of 1 and 5 A g −1 , respectively, exhibiting high electrochemical stability and high reversible capacity. Further research reveals that the fabrication of hierarchically porous anatase TiO 2 depends on the amounts of HAc added, and the pH of the solution. Two-dimensional hierarchically porous anatase TiO 2 is fabricated through acetic acid etching. It exhibit high electrochemical stability and high reversible capacity in lithium ion battery.