Template-free electrochemical synthesis of Cd/CdTe core/shell nanowires and CdTe nanotubes

Abstract

Template-free electrodeposition is a facile, low-cost and environmentally friendly method for the synthesis of one-dimensional (1D) nanostructures. In this study, the template-free electrodeposition was successfully utilized to synthesize 1D nanostructures of CdTe nanotubes and Cd/CdTe core/shell nanowires. In an alkaline electrolyte containing Cd and Te sources, Cd/CdTe core/shell nanowires and CdTe nanotubes were directly electrodeposited on ITO-coated glass substrates under a stationary cathodic potential. The Cd cores of the nanowires are single crystalline with a cubic structure and preferential growth along the <001> direction, while the CdTe shells of the nanowires and the CdTe nanotubes are polycrystalline. It is proposed that Cd nanowires were first formed along the <001> direction due to the anisotropic crystal growth of Cd. Then, the Cd nanowires were electrochemically converted into CdTe, and Cd/CdTe core/shell nanowires and CdTe nanotubes were formed based on the Kirkendall effect.