Figure 5. Comparison of electrochemical performances of the as-prepared samples.

(a) Charge-discharge curves for pure SnO₂, Co/SnO₂ and Co-N/SnO₂/Li cycled between 3.0 and 0.005 V at a rate of 0.1 C (1 C = 782 mA g⁻¹). CV curves of the pure SnO₂ (b), Co/SnO₂ (c) and Co-N/SnO₂ (d) electrodes at a scanning rate of 0.10 mV s⁻¹. Cycling performances at 0.1 C (e) and rate capabilities (f) of SnO₂, Co/SnO₂ and Co-N/SnO₂ electrodes (“dis” and “cha” represent the states of discharge and charge upon cycling).