S. F. Nik

Growth Mechanism Of Carbon Nanotubes Prepared By Fluidized Floating Catalyst Method

In this paper, carbon nanotubes were synthesized by fluidized floating catalyst method which yielded high yield even at low temperature; 650° C using camphor oil as carbon source and Argon as carrier gas. Optimum concentration for trimetal alloy catalyst; Fe/Ni/Mg has been found to be the suitable catalyst for producing carbon nanotubes at high yield. Carbon nanotubes are formed by the evaporation of the camphor oil (precursor), which decomposes ‘in situ’ and aggregates on the metal alloy catalyst particles present in the ceramic boat. The morphology of carbon nanotubes were characterized by field emission scanning electron microscopy (FESEM). This result demonstrates that fluidized floating catalyst method is suitable for effective formation of CNTs with average size ∼11.5 nm. The morphological studies support ‘tip growth mechanism’ for the growth of the CNT’s in our case.

Optimization of Fe/Ni/Mg Trimetallic Catalyst for Carbon Nanotubes Growth by Using Fluidized Floating Catalyst Method

Fluidized floating catalyst method has been used for preparing carbon nanotubes with average size ∼11 nm which yielded high yield even at low temperature; 650° C. Optimum concentration of the Fe/Ni/Mg metal alloy catalyst has been found to be at 2.133% for producing carbon nanotubes with high yield. Carbon nanotubes are formed by the evaporation of the camphor oil (precursor), which decomposes ‘in situ’ and aggregates on the metal alloy catalyst particles present in the ceramic boat. From the PXRD analyses, graphite layers detected which provide an indication of the degree of graphitic character. However, by using the Scherrer equation is not suitable for carbon nanotubes as the value is slightly different from the average diameter determine from FESEM micrographs. Since the metallic alloy was obtained by calcining the respective nitrates, it is expected to have residual entrapped nitrogen, which may bond with the depositing CNTs as observed from FTIR spectroscopy.

Vertically Aligned Carbon Nanotubes from Palm Oil Precursor

This paper reports a study on vertically aligned carbon nanotubes (VACNTs) synthesized by thermal chemical vapor deposition (TCVD) method using eco-friendly carbon source; palm oil. Palm oil vaporized at 450oC in argon atmosphere at ambient pressure. For better decomposition of palm oil complex structure, ferrocene were added into palm oil and stirred for 20 minutes prior to synthesis process. The synthesis and annealing duration took 30 and 10 minutes respectively. The field emission scanning electron microscopy (FESEM) and infrared spectroscopy analysis were systematically studied on CNTs produced. The detailed of CNTs properties will be discussed further.

The Electrical and Optical Properties of PMMA/MWCNTs Nanocomposite Thin Films

The poly(methyl methacrylate) (PMMA)/multi‐walled carbon nanotubes (MWCNTs) nanocomposite thin films have been prepared by spin‐coating technique. The electrical properties as well as UV‐Visible spectrophotometer have been studied as a function of the MWCNTs’ weight percentage. The electrical conductivity of the films increases by several orders of magnitude upon the addition of MWCNTs into PMMA solution. It was observed that the conductivity enhancement is interpreted by the formation of a continuous electron paths or conducting network in the polymer nanocomposite indicated by the efficient dispersion of MWCNTs into PMMA. The optical band gap of the films was assessed using Tauc approximation from the UV‐Vis spectra. The surface morphology was investigated using the scanning electron microscope (SEM) to study on the MWCNTs’ dispersion in the polymer matrix.

Properties Of Carbon Nanotubes Produced Using Fe/Co/Al Trimetallic Catalyst In Fluidized Floating Catalyst Method

Carbon nanotubes (CNTs) were synthesized by fluidized floating catalyst method by using camphor oil as the carbon source and Fe/Co/Al as the catalyst. The catalyst was prepared by sol‐gel method using nitrate salt. Carbon nanotubes were produced by using fluidized floating catalyst method, in low temperature condition; 650° C. The results showed that a thickened submicron vapor grown of multi‐wall nanotubes that produced only with a vaporize catalyst and the hydrocarbon source with diameters of about ∼30 nm. In fact, very few carbon nanotubes have either a particle tip at the end or trapped metal particle inside the wide hollow core of this type of produced carbon material. Structural characterizations have been done by FESEM, FTIR and XRD analyses.

The Effect of Temperature on Carbon Nanotubes Grown Using Monometallic Catalyst from Palm Oil Precursor

The effects of temperature on carbon nanotubes (CNTs) by thermal chemical vapor deposition (TCVD) method were systematically studied. Natural hydrocarbon source; palm oil was used as precursor and argon as carrier gas. Palm oil vaporized optimally at 450oC in ambient pressure. The synthesis temperature start at 650°C and were increased at rate of 50°C for series of samples until it reaches maximum temperature of 900°C. The samples were grown on nickel nitrate, which was coated on silicon substrate. The CNTs characteristics were studied using field emission scanning electron microscopy (FESEM), Raman and infrared (IR) spectroscopy. The experimental results revealed that CNTs properties are highly dependent on temperature. It was found that with increasing synthesis temperature, the CNTs diameter decreased initially and then increased after passing an optimum synthesis temperature of 750°C. The bamboo like structure were obviously found at higher synthesis temperature 800°C-850°C while there were few CNTs seen at 900°C.

The Effect of Inoculum in the Preparation of Fermented Tapioca for Nanotechnology Applications Based on the Surface Morphology of CNTs

Fermented tapioca which is a new starting material was used as a carbon precursor. Carbon nanotubes (CNTs) were deposited on silicon wafer (Si) by Thermal Chemical Vapor Deposition (TCVD). The gas flow of Argon (Ar) was constant at 70 bubbles per minute and 20 minutes of deposition time. Before the deposition process, silicon was coated with Nickel using spin coater. Various parameters such as amount of inoculums have been studied. Surface morphology and uniformity were characterized using FESEM. The surface morphology and uniformity of CNTs are dependents on parameters used. The optimum CNTs that produced using Thermal CVD was 1.5 wt% of inoculums due to the size and the uniformity of CNTs growth.

The effect of inoculum in the preparation of fermented tapioca for nanotechnology applications based on FT-IR studies

Fermented tapioca which is a new starting material was used as a carbon precursor. Carbon nanotubes (CNTs) were deposited on silicon wafer (Si) by Thermal Chemical Vapor Deposition (TCVD). The gas flow of Argon (Ar) was constant at 70 bubbles per minute and 20 minutes of deposition time. Before the deposition process, silicon was coated with Nickel using spin coater. Various parameters such as amount of inoculums have been studied. Chemical functional groups of carbon nanotubes were characterized using FT-IR Spectroscopy. The FT-IR result shows peaks attributed to multi–walled carbon nanotubes (MWCNT) vibration modes.

FTIR Studies of Carbon Nanotubes Produced from Fermented Tapioca Prepared by Thermal-CVD

Fermented tapioca prepared at different temperature was prepared and used as a starting material in CNTs synthesis using 2-system thermal chemical vapor deposition (TCVD) method. The CNTs was deposited on nickel coated silicon where the nickel acts as catalyst in the growth process. The size of CNTs growth is dependent to the temperature. The prepared CNTs were analyzed using Fourier transformation infrared spectroscopy (FTIR) to determine the chemical properties in the sample. Fourier transform infrared (FTIR) spectroscopy was carried out in the range of 450-4000 cm-1 to study the attachment of the impurities on carbon nanotubes.

Malaysian palm oil for carbon nanotubes preparation

Carbon nanotubes The discovery of ‘fullerenes’ added a new dimension to the knowledge of carbon science1; and the discovery of ‘carbon nanotubes’ (CNTs, elongated fullerene) added a new dimension to knowledge of technology2. Today, ‘nanotechnology’ is a hot topic attracting scientist, industrialists, journalist, governments, and even the general public. Nanotechnology is the creation of functional materials, devices and systems through control of matter on the nanometer scale and the exploitation of novel phenomena and properties of matter (physical, chemical, biological, electrical, etc.) at that length scale. CNTs are supposed to be the key component of nanotechnology. Almost every week a new potential application of CNTs is identified, stimulating scientists to peep into this tiny tube with ever increasing curiosity.