Figure 5: Electrochemical performances.

(a) Charge/discharge curves for the second cycles of PG, GO, EG-1 h and EG-5 h at a current density of 20 mA g⁻¹. (b) Short-term cycling stability test for PG, GO, EG-1 h and EG-5 h at a current density of 20 mA g⁻¹. (c) Long-term cycling stability of EG-1 h. Note that 20 mA g⁻¹ was used for the initial 10 cycles. At the 11th cycle, the current was changed to 100 mA g⁻¹ and held constant during the rest of the test. (d) Rate capability test for EG-1 h. Note that the cell was pre-cycled at 20 mA g⁻¹ for 20 cycles before the rate performance test. Capacities shown in b–d are specific desodiation capacities.