One-step Hydrothermal Synthesis of CdTe Nanowires with Amorphous Carbon Sheaths

Abstract

One-dimensional (1D) CdTe nanostructures. II-VI group semiconductor material with direct band gap of 1.45 eV and high absorption coefficient, have become the focus of research interest due to their potential use as ideal building blocks in fabricating nanoscaJe eJectronics, optical and sensorial devices. However, the adsorption of unwanted species (such as water and oxygen) on the surface and unnecessary charge injection into CdTe nanowires couJd negativeJy affect characteristics or stabiJity of the devices. One possibJe soJution of these probJems couJd be to fabricate the CdTe nanowires with insulating sheaths. In this work. carbon-coated CdTe nanowires were successfully synthesized through a faciJe one-step hydrothermaJ process by using ascorbic acid as a reducing agent and carbonization source. SequentiaJ mechanism for the phase formation, shape evoJution. and carbon sheath formation was also investigated from the experiment resuJts for various reaction times in detai J. The phase of obtained products was characterized by X-ray diffraction (XRD). FieJd emission scanning electron microscopy (FE-SEM), and transmission eJectron microscopy (TEM) were expJoited to observe the morphoJogy and size of the products. In order to anaJyze the sheaths on the surface of CdTe nanowires, the room temperature Raman spectra were also recorded.