Metal organic framework-derived carbon nanosheets with 2D adjustable defective sub-units for outstanding Li- and Na-ion storage

The structural design and functional properties of carbon materials are considered to improve electrochemical performance of the electrode materials. In this study, a solvothermal method is applied to realize nanostructure engineering of MOF-derived carbon nanostructures. Carbon nanosheets with 2D adjustable defective sub-units are designed for the first time. The optimal nanostructures with large specific surface area and appropriate pore size distribution can effectively avoid irreversible damage when charge-discharge cycles. Therefore, a remarkable electrochemical performance is obtained for both Li-ion and Na-ion battery systems. For Li-ion batteries, a specific capacity of 825 mAh g⁻¹ is achieved after 100 cycles at 0.1 C, while for Na-ion batteries a specific capacity of 193 mAh g⁻¹ is observed after 100 cycles at 0.5 C. Moreover, for Na-ion batteries, even at a high rate of 5 C, the material delivers a specific capacity of 109.5 mAh g⁻¹ after 3500 cycles.