A Co-based metal-organic framework （Co-MOF） with a unique three-dimensional starfish-like nanostructure was successfully synthesized using a simple ultrasonic method. After subsequent carbonization and oxidation, a ...A Co-based metal-organic framework （Co-MOF） with a unique three-dimensional starfish-like nanostructure was successfully synthesized using a simple ultrasonic method. After subsequent carbonization and oxidation, a nanocomposite of nitrogen-doped carbon with a Co3O4 coating （Co3O4@N-C） with a porous starfish-like nanostructure was obtained. The final hybrid exhibited excellent lithium storage performance when evaluated as an anode material in a lithiumion battery. A remarkable and stable discharge capacity of 795 mAh·g^-1 was maintained at 0.5 A·g^-1 after 300 cycles. Excellent rate capability was also obtained. In addition, a full Co3O4@N-C/LiFePO4 battery displayed stable capacity retention of 95% after 100 cycles. This excellent lithium storage performance is attributed to the unique porous starfish-like structure, which effectively buffers the volume expansion that occurs during Li^＋ insertion/deinsertion. Meanwhile, the nitrogendoped carbon coating enhances the electrical conductivity and provides a buffer layer to accommodate the volume change and accelerate the formation of a stable solid electrolyte interface layer.展开更多
基金Acknowledgements This work is supported by the National Natural Science Foundation of China （Nos. 21173001 and 21371003） and Anhui Province Key Laboratory of Environment-Friendly Polymer Materials.
文摘A Co-based metal-organic framework （Co-MOF） with a unique three-dimensional starfish-like nanostructure was successfully synthesized using a simple ultrasonic method. After subsequent carbonization and oxidation, a nanocomposite of nitrogen-doped carbon with a Co3O4 coating （Co3O4@N-C） with a porous starfish-like nanostructure was obtained. The final hybrid exhibited excellent lithium storage performance when evaluated as an anode material in a lithiumion battery. A remarkable and stable discharge capacity of 795 mAh·g^-1 was maintained at 0.5 A·g^-1 after 300 cycles. Excellent rate capability was also obtained. In addition, a full Co3O4@N-C/LiFePO4 battery displayed stable capacity retention of 95% after 100 cycles. This excellent lithium storage performance is attributed to the unique porous starfish-like structure, which effectively buffers the volume expansion that occurs during Li^＋ insertion/deinsertion. Meanwhile, the nitrogendoped carbon coating enhances the electrical conductivity and provides a buffer layer to accommodate the volume change and accelerate the formation of a stable solid electrolyte interface layer.
