Chestnut shell-like Li4Ti5O12 hollow spheres for high-performance aqueous asymmetric supercapacitors

- 3D chestnut shell-like Li4Ti5O12 hollow sphere is fabricated.
- Li4Ti5O12 hollow sphere displays remarkable capacitance over 2000 cycle.
- Aqueous asymmetric supercapacitor is constructed based on Li4Ti5O12 and N doped GO.

As promising electrode materials in supercapacitor, metal oxides have attracted significant attention recently. At present, it is highly desirable but remains challenging to prepare three-dimensional (3D) metal oxides hollow materials for further improving the performance of supercapacitors. Herein, 3D chestnut shell-like Li4Ti5O12 hollow sphere is successfully fabricated by using an effective hydrothermal strategy. Owing to the unique structural feature and the desirable chemical composition, Li4Ti5O12 hollow sphere displays a remarkable capacitance of 653.22 F/g at 1 A/g and keeps 88.56% over 4000 cycle. Furthermore, one aqueous asymmetric supercapacitor (ASC) is constructed based on Li4Ti5O12 and N-doped graphene oxide (NGO) which is synthesized by a facile burning method. The Li4Ti5O12//NGO ASC shows an energy density of 26.15 Wh/kg at power density of 799.83 W/kg, and yet keeps 14.45 Wh/kg even at 8.01 kW/kg. This strategy may offer a versatile idea of tailoring new type of 3D metal oxides hollow materials and opens the possibility for using in high energy storage device.

109We have successfully synthesized 3D Li4Ti5O12 hollow sphere for high-performance.