Surface functionalization to control the wetting behavior of nanostructured carbons

Thin films of C were deposited on Si wafers, glassy C, and SiO2 substrates by CVD using ethylene as the C source. The films were treated with NaOH, HNO3, and HF to make their surface more hydrophilic and with parylene, polydimethylsiloxane, and VTMOS to make their surface more hydrophobic. The samples were characterized by SEM, TEM, and Raman spectroscopy. The wetting behavior of the surface-modified films was studied by contact angle measurements under the following liqs.: H2O, EtOH, 1,2-ethanediol, THF, glycerol, ethylene glycol, cyclohexane, hexadecane, polydimethylsiloxane, and poly(3,3,3-trifluoropropylsiloxane). Furthermore, the wetting behavior was investigated for as deposited films which were annealed between 900-2000 Deg under vacuum.