Fig. 5: Electrochemical properties of the TQBQ-COF electrodes between the voltage range from 1.0 V to 3.6 V.

a CV curves of the TQBQ-COF electrode at a scan rate of 0.2 mV s⁻¹. b Charge–discharge profiles of the TQBQ-COF electrode at 0.02 A g⁻¹. c The rate performance of the TQBQ-COF electrode from the current density of 0.1 to 10 A g⁻¹, then back to 0.1 A g⁻¹. d Long cycling stability of TQBQ-COF electrodes at different current densities (0.1, 0.5, and 1.0 A g⁻¹). The capacities are all calculated based on the mass of TQBQ-COF. e The selected charge/discharge curves of pouch-type Na//TQBQ-COF batteries at a current of 50 mA. The capacity is calculated based on the mass of the full cell.