Alkali-etching Bi-MOF to create oxygen-deficient α-Bi2O3 nanobelt as high-capacity Ni-Bi battery anode

Bi 2 O 3 has been recognized as a promising anode of aqueous secondary battery because of the high capacity, but the application is greatly hindered by the poor conductivity and limited actual capacity. Herein, for the first time, one dimensional (1D) α-Bi 2 O 3 nanobelt is fabricated via alkali etching strategy using rod-shaped Bi-MOF (CAU-17) as the self-sacrificial template. Specifically, high-crystalline and oxygen-deficient α-Bi 2 O 3 nanobelt with length and width of 6 μm and 300 nm are identified. The electrochemical results demonstrate the high specific capacity (247 mAh g −1 @1 A g −1 ) and acceptable stability of α-Bi 2 O 3 nanobelt. Such superior capacity is derived from the exposed electrochemical active sites, fast charge transfer and efficient ion diffusion in 1D high-crystalline and oxygen-vacancies enriched structure. The assembled Ni-Bi battery displays high capacity (78.3 mAh g −1 ) and high energy density of 100.2 Wh kg −1 (at power density of 2829.8 W kg −1 ). Our work provides rational guidance for architecting 1D high-capacitive electrodes for aqueous rechargeable alkaline battery.