T-Nb₂O₅ quantum dots prepared by electrodeposition for fast Li ion intercalation/deintercalation

T-Nb₂O₅ quantum dots were electrodeposited on Ti nanorod arrays to prepare Ti@T-Nb₂O₅ core-shell array electrodes. The particle size of T-Nb₂O₅ could be manipulated by adjusting the depositing current density, and quantum dots several nanometers in size could be obtained at a deposition current of 6 mA cm^-2. Benefiting from the ultra-small particle size of T-Nb₂O₅ and the array structure, Ti@T-Nb₂O₅ nanorod arrays exhibited good rate capability and durability when used as self-supported Li ion battery anodes. The arrays possessed capacities of 350 and 70 mAh g^-1 at rate currents of 0.06 and 30 A g^-1, respectively. Furthermore, the electrodes maintained 500 cycles without obvious decay at a high rate current of 30 A g^-1.