How to make a rough surface with super-hdrophobicity while still having low friction? Jian Sui et al gave an answer. They successfully synthesized a porous carbon coating on titanium silicon carbide with combined self-lubricating and super-hydrophobicity properties through selective chlorination and surface modification. The friction coefficient of this coating against silicon nitride is comparable to that of commercially available graphite and much lower than that of polished titanium silicon carbide. Meanwhile, the hydrophobicity could be seen from the high water contact angle above 150° and was stable in various environments. Because of the high chemical resistance of carbides, simple and smart chlorination etching is significative and attractive for constructing multi-functional surface on carbide substrates.
Source: Carbon, Volume 47, Issue 3, Page 629-634 (March 2009)