A facile room-temperature chemical reduction method to TiO2@CdS core/sheath heterostructure nanowires

We have prepared functional TiO2@CdS core/sheath heterostructure nanowires using a simple chemical reduction method at room temperature. The core/sheath nanowires were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD) and UV-visible spectroscopic techniques. It was found that the thickness of the CdS sheath could be controlled by the concentration of the precursors. The continuous and polycrystalline CdS outer layer could be formed on the TiO2 nanowires when the concentration of the S precursor was higher than 0.2 mmol. A possible multi-site growth mechanism of the formation of the composite nanowires was proposed.