In this study, Si-doped carbon nanotubes (SiCNTs) were synthesized using Fe/CaCO 3 as catalyst, acetylene, and silane as precursors by chemical vapor deposition (CVD). In the second project, hydrophobic carbon spheres (CSs) in micron sizes were synthesized using bentonite substrate catalyst and acetylene as precursor. The reaction’s temperature was considered as a variable in both studies and its effect on the structure of product was investigated. The obtained electronic microscope’s images confirmed the shapes of both products. The insertion of silicon atom in the structure of carbon nanotubes showed some changes in the properties and structure of this product, which have been investigate using FESEM, TEM, XRD, Raman, EDS and TGA. The electrocatalytic properties of SiCNTs were examined in Hydrogen evolution reaction (HER) and the results confirmed this activity. Hydrophobic carbon spheres were also considered as a selective removal of oil from water.
