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This paper addresses the growth of nano-structured MgZnO thin films by sol-gel spin coating method which will be used as a template layer to grow carbon nanotubes. The nano-structured MgZnO films were deposited on platinized (100) silicon substrates. In this work, we focused on the effect of aging and Mg content on the film structure and resistivity. Sols with Mg content of 10, 30 and 50 at.% were subjected to aging times of between 3 to 240 hours. Results from scanning (SEM) and field emission scanning electron (FESEM) microscopes and surface profiler (SP) showed that the sol aging increased the thickness, grain size and surface roughness for aging up to 240 hours. The energy dispersive analysis by X-ray (EDAX) confirmed the element of Mg in the ZnO films. The electrical resistivity also increased with aging time as confirmed by four point probe method. The results suggest that appropriate aging of the sol is important for improving physical quality and electrical performance of MgZnO thin films derived from sol-gel technique.

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We report the use of a new precursor as active agents to promote the growth of carbon nanotubes (CNT) in methane ambient using a simple thermal chemical vapour deposition method. The agents consist of ammonia and methanol mixed at different ratios and was found to enhance the growth of CNTs. The optimum methanol to ammonia ratio was found to be 8 to 5, whereby longer and denser CNTs were produced compared to other ratios. The result was found otherwise when the experiment was done solely in methane ambient. In addition, CNT growth on substrates coated with double layer Ni catalyst was improved in terms of quality and density compared to a single coated substrates. This finding is supported by Raman spectrometry analysis.

In this article the effect of catalyst thickness and reaction temperature on the formation of horizontal multi-wall carbon nanotube (MWCNT) was discussed to control product growth and morphology. MWCNTs were synthesized from methane by double-heater thermal catalytic vapor deposition method (TCVD) using a mixture of methanol and ammonia as active agents to promote the growth of nanotubes and nickel as a catalyst and are characterized by scanning electron microscopy (SEM) and Raman spectroscopy.Results from SEM indicated that, the diameter and density of tubes increased with increasing the catalyst thickness, whereas the effect of reaction temperature was on the growth efficiency and purity of nanotubes and lifetime of the catalyst. The most favorable temperature for the highest growth efficiency and purity was around 900 °C. However the optimal catalyst thickness was around 4 nm.