No abstract

The growth of carbon-based nanomaterials on diatoms allows the environmentally friendly production of new materials with potential applications for energy storage. Here, we report the growth control of multi-walled carbon nanotubes (MWCNTs) and carbon spheres (CCs) on diatoms using cobalt ferrite (CoFe2O4) and FeCo nanoparticles as catalysts. Carbon nanomaterials were obtained by the catalytic Chemical Vapor Deposition method (CVD) at 750◦C with acetylene as a carbon source. The formation of MWCNTs and carbon spheres on the diatom was confirmed by Fourier Transform Infrared spectroscopy (FTIR), X-ray Diffraction (XRD), Scanning Electron Microscopy (SEM), Raman spectroscopy, and X-ray photoelectron spectroscopy (XPS). Our results reveal that the MWCNTs were formed using the FeCo nanoparticles and the carbon spheres with CoFe2O4 nanoparticles as catalysts. The effect of the catalyst and the formation mechanism was discussed. The advantage of these results relies on using diatoms as a substrate to control the growth of high-quality carbon nanomaterials by tailoring the surface with different catalytic sources.