Figure 6. Electrochemical performances of as-prepared hierarchical hollow nanocapsules (etching time of 40 min):

(a) cyclic voltammetry plots of SnO₂@TiO₂ electrode at the scan rate of 0.05 mV s⁻¹. (b) charge/discharge curves of SnO₂@TiO₂ electrode for the 1^st, 2^nd, and 200^th cycle at current density of 1 C; (c) the cycling performance of bare SnO₂ and SnO₂@TiO₂ measured at 1 C. (d) rate capability of SnO₂@TiO₂ electrode from 0.5 C to 20 C for 200 cycles. Electrode potential range; 0.01–3.0 V vs. Li/Li⁺.