Synthesis of ZnO nanowires (NWs) using vapor phase transport (VPT) assisted with thermal evaporation of brass (CuZn) assisted by hotwire was presented. The effects of aliphatic alcohols such as methanol and ethanol as source of oxygen were investigated using field emission scanning electron microscope and X-ray diffraction (XRD). Significant changes in the morphology and structure of both ZnO NWs prepared using methanol (ZnO/M NWs) and ethanol (ZnO/E NWs) depicted the influence of aliphatic alcohols. Debye Scherer (DS), Williamson-Hall (W-H) and size-strain plot (SSP) analysis on the XRD peak broadening revealed that ZnO/M NWs revealed lower strain and stress value compared to ZnO/E NWs. ZnO/M NWs, which was preferential to 002 crystallographic orientation found to be hexagonal isotropic crystalline nature whereas ZnO/E NWs preferential of 101 crystallographic orientation is anisotropic crystalline nature.

Vapor phase transport (VPT) assisted by mixture of methanol and acetone via thermal evaporation of brass (CuZn) was used to prepare un-doped and Al-doped zinc oxide (ZnO) nanostructures (NSs). The structure and morphology were characterized by field emission scanning electron microscopy (FESEM) and x-ray diffraction (XRD). Photoluminescence (PL) properties of un-doped and Al-doped ZnO showed significant changes in the optical properties providing evidence for several types of defects such as zinc interstitials (Zni), oxygen interstitials (Oi), zinc vacancy (Vzn), singly charged zinc vacancy (VZn -), oxygen vacancy (Vo), singly charged oxygen vacancy (Vo +) and oxygen anti-site defects (OZn) in the grown NSs. The Al-doped ZnO NSs have exhibited shifted PL peaks at near band edge (NBE) and red luminescence compared to the un-doped ZnO. The Raman scattering results provided evidence of Al doping into the ZnO NSs due to peak shift from 145 cm-1 to an anomalous peak at 138 cm-1. Presence of enhanced Raman signal at around 274 and 743 cm-1 further confirmed Al in ZnO NSs. The enhanced D and G band in all Al-doped ZnO NSs shows possible functionalization and doping process in ZnO NSs.

The [O] [H] functionalization of carbon nanotube (CNT) was studied using oxygen-hydrogen (O 2 -H 2 ) gas mixture direct current (DC) glow discharge plasma technique for cathode/CNT-anode separation of 0.10 ± 0.01 cm. O 2 and H 2 were fixed at flowrate of 10.0 ml/min in order to obtain gas mixture ratio of 1:1. During the (O 2 -H 2 ) gas mixture DC glow discharge, current-voltage (I-V) characteristic of gaseous species studied for various settings of gas pressures 1, 2, 3 and 4 mbar. The voltage at gap between cathode/CNT and anode, a breakdown voltage, was identified as ''functionalization voltage'' (V func ). V func was noticed responsible for functionalization of functional groups on sidewall of CNT. The V func were recorded as 796, 707, 594, and 663 V for gas pressures of 1, 2, 3 and 4 mbar, respectively. The co-relation between V func and gas pressure was identified as linear relationship. But a voltage obtained due to the CNT/Cathode fall shows exponential relationship with the gas pressures. The possibility of [O] [H] functionalization was proved using Fourier transmission infra-red (FTIR) spectroscopy. Hydroxyl (-OH), carboxyl (-COOH), and carbonyl (-C=O) functional groups were identical as identified in the FTIR spectra. The field emission scanning electron microscope images show significant changes in the morphology of CNT which proves that the DC gas discharge plasma is a possible technique for [O] [H] functionalization on the sidewall of CNT.

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Zinc oxide (ZnO) nanowires (NWs) were synthesized using vapor phase transport (VPT) and thermal evaporation of Zn from CuZn. Time dependence of ZnO NWs growth was investigated for 5, 10, 15, 20, 25, and 30 minutes. Significant changes were observed from the field electron scanning electron microscopy (FESEM) images as well as from the X-ray diffraction (XRD) profile. The photoluminescence (PL) profile was attributed to the contribution of oxygen vacancy, zinc interstitials, and hydrogen defects in the ZnO NWs. Raman scattering results show a significant peak at 143 cm−1and possible functionalization on the wall of ZnO NWs. Growth of ZnO NWs in (0002) with an estimated distance between adjacent lattice planes 0.26 nm was determined from transmission electron microscopy (TEM) analysis.