Hierarchical Li4Ti5O12-TiO2 microspheres assembled from nanoflakes with exposed Li4Ti5O12 (011) and anatase TiO2 (001) facets for high-performance lithium-ion batteries

• DOI: 10.1016/j.electacta.2016.11.081
• Publication Date: 2016-11-15T19:01:01Z
• Authors: Guangyin Liu; Xiaodi Liu; Lin Wang; Jianmin Ma; Haiquan Xie; Xiaoguang Ji; Jiali Guo; Ruixue Zhang
• Keywords: 02 engineering and technology; 0210 nano-technology; 7. Clean energy

Abstract Hierarchical Li 4 Ti 5 O 12 -TiO 2 microspheres are synthesized via an oil/water interface method with the assistance of cetyltrimethylammonium bromide (CTAB) and following calcination. The as-prepared Li 4 Ti 5 O 12 -TiO 2 microspheres are consisted of nanoflakes ( ca. 15 nm in thickness); moreover, Li 4 Ti 5 O 12 and anatase TiO 2 in the nanoflake building blocks are bounded by (011) and (001) facets, respectively. More especially, it is found that CTAB plays a very important role in the phase and morphology of the Li 4 Ti 5 O 12 -TiO 2 composite. When employed as the anode materials for lithium-ion batteries, the Li 4 Ti 5 O 12 -TiO 2 microspheres show initial discharge capacities of 234, 170, 151 and 140 mAh g −1 at charge/discharge rate of 1, 5, 10, and 20C, respectively; furthermore, after 100 cycles at 5C, the discharge capacity remains at 158 mAh g −1 with a capacity retention of 92.9%. The excellent electrochemical properties of the product can be ascribed to the synergistic effect of the exposed Li 4 Ti 5 O 12 (011) and anatase TiO 2 (001) facets, abundant phase interfaces, hierarchical structures, and thin flake-like building blocks.