Figure 7

(a) Charge/discharge curves at a current density of 2 A g−1. Charge/discharge curves at different current densities of 2, 4, 10, 20, and 40 A g−1 for (b) NCS@C-20, (c) NCS@C-40, and (d) NCS@C-80.

(a) Charge/discharge curves at a current density of 2 A g−1. Charge/discharge curves at different current densities of 2, 4, 10, 20, and 40 A g−1 for (b) NCS@C-20, (c) NCS@C-40, and (d) NCS@C-80.