Structural and photoluminescence properties of Zinc oxide nanowires synthesized by smart thermal CVD method

1D ZnO nanowires (NWs) are attractive material properties and unique performance in electronics, optics and photonic devices. In this paper, a smart thermal chemical vapor deposition (CVD) technique has been used to synthesize high crystalline and large scale ZnO NWs on Si substrate without any catalyst. The structural, surface morphology and luminescence properties of the deposited nanothin films are characterized by X-ray diffraction (XRD) technique, field emission scanning electron microscope (FESEM), energy dispersive X-ray spectrometer (EDX) and photoluminescence (PL) spectroscopy measurements. It is shown that ZnO NW has a hexagonal cylindrical structure with orientation of (002). The FESEM results of ZnO nanowires have shown smooth surface morphologies having diameter ~ 60-80 nm and length ~ 5-8 µm. The room temperature PL measurement exhibited sharp exciton line at 3.26 eV and a weak defect related red band at 1.58 eV. Furthermore, the possible formation of large scale ZnO NWs is presented. The smart thermal CVD method provides an excellent approach to control ZnO NWs growth for optoelectronic devices applications.