The structural and surface properties of carbon nanotube synthesized by microwave plasma chemical vapor deposition method for superhydrophobic coating

We selected the carbon nanotubes (CNTs) as the material for super hydrophobic surface. We used a microwave plasma chemical vapor deposition method with low temperature, methane and hydrogen gases to fabricate CNTs. The Ni layer as the catalyst layer was deposited on the Ti-coated Si substrate by rf magnetron sputtering method. In this work, we investigated the structural and surface characteristics of CNTs synthesized with various working pressures. The working pressure is changed from 10.7 × 102 Pa to 32 × 102 Pa. In the results, the average diameter of CNTs grown with various working pressures is from 40 to 60 nm and the average length of the grown CNTs has about several μm. Also, CNTs grown at various conditions show Ni tips are multi-shell graphite sheets with Ni tips and multi-wall structure. From the results of Raman spectroscopy, the positions of D- and G- peaks of CNTs are located around 1345 cm− 1 and 1580 cm− 1, respectively, and ID/IG ratio decreased with increasing working pressure. The contact angle value of CNT grown at 10.7 × 102 Pa was about 116° and the contact angle value decreased with increasing working pressure, indicating hydrophilic property.