fig4

Figure 4. Electrochemical properties for lithium-ion storage. (A) GCD curves and (B) corresponding dQ/dV plots of the meso-Nb₂O₅-500, meso-Nb₂O₅-700 and NP-40 nm electrodes in the 2nd cycle at the specific current of 0.02 A·g^-1; (C) Rate capability at different specific currents; and (D) Cycling stability of the three electrodes at 0.1 A·g^-1. GCD: Galvanostatic charge and discharge.