Plasma Treatment of Ga-Doped ZnO Nanorods

A comparative study of structural, optical properties of plasma-treated Ga-doped ZnO nanorods (GZO NRs) prepared by hydrothermal growth is presented, which provides an economical technology for fast production. Annealing in air followed by plasma treatment has been found to be an effective way of purification of ZnO NRs. The plasma hydrogenation and oxidation are done at room temperature in an inductively coupled plasma (ICP) reactor. The properties of plasma-treated GZO NRs are investigated using various characterization methods, such as scanning electron microscopy (SEM), Raman, Fourier transform infrared (FTIR), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), and electron paramagnetic resonance (EPR) spectroscopy. The SEM confirms the hexagonal shape of all GZO NRs. XPS reveals the presence of metallic Ga as well as Ga2O3 on GZO NRs surface. XRD has detected hexagonal (P63mc) ZnO phase in all samples with additional diffraction pattern in powder that has not been plasma treated. Plasma treatment does not affect the position of FTIR signals but changes the intensity of some absorption peaks. EPR shows a dominant signal with a g-factor of 1.96. Plasma treatment of GZO samples affects its intensity.