Production of Fe-doped Al2O3 ceramic powders and substrates for carbon nanotube synthesis

In this study, alpha-Al2(1-x)Fe2xO3 powders with high specific surface area were synthesized by homogeneous precipitation and combustion synthesis methods. These powders were utilized for the production of carbon nanotubes (CNTs) via catalytic chemical vapor deposition (CCVD) method, and the effect of these two powder synthesis methods on CNT quantity and quality was investigated. The characterization results of CNT-Fe-Al2O3 nanocomposite powders revealed that both homogeneously precipitated and combustion synthesized powders could be utilized as precursor materials for CNT synthesis. However, in terms of powder yield, CNT amount in the nanocomposite powders, and purity of the CNTs, combustion synthesized powders were determined to be utilized in the further polycrystalline Fe-doped Al2O3 substrate production studies.Fe-doped Al2O3 ceramics with varying degrees of texture were prepared via Templated Grain Growth (TGG) method and utilized as a substrate for CNT growth via CCVD. Scanning electron microscope (SEM) analyses indicated that uniform distribution of catalyst nanoparticles (Fe) over the substrate surface was achieved. Depending on the texturing level of the substrates, randomly oriented or vertically aligned carbon nanotubes were grown over these substrates.Keywords:Fe-doped Al2O3, textured microstructure, catalytic chemical vapor deposition (CCVD), carbon nanotube, nanocomposite