Fabrication and characterization of electrodeposited antimony telluride crystalline nanowires and nanotubes

Abstract

Arrays of nanowires and nanotubes of antimony-telluride (Sb₂Te₃) have been fabricated by an electrodeposition technique. Scanning electron microscopy was employed to characterize the morphology and size of the fabricated Sb₂Te₃ nanowires and nanotubes. Wavelength dispersive spectroscopy analysis confirmed the composition of the fabricated nanowires and nanotubes. The composition of the nanowires fabricated at a cathodic current density of 10 mA cm⁻² and nanotubes fabricated at a cathodic current density of 5.5 mA cm⁻² was found to be ∼39% Sb and ∼61% Te (2 : 3 ratio between Sb and Te). The fabricated Sb₂Te₃ nanowire and nanotube arrays were found to be polycrystalline with no preferred orientation. The average lamellar thickness of the nanowires and nanotube crystallites was determined using the Scherrer equation and found to be ∼36 nm and ∼43 nm, respectively. The measured room temperature Seebeck coefficients for the Sb₂Te₃ nanowires and nanotubes were +359 µV K⁻¹ and +332 µV K⁻¹, respectively, confirming that the Sb₂Te₃ nanowires and nanotubes were p-type. The electrical resistance measurements indicated that the resistance of the Sb₂Te₃ nanowires and nanotubes decreased with increasing temperature, consistent with semiconducting behavior.