Mesostructured carbon film with morphology-induced hydrophilic surface through a dewetting-free coating process

Hydrophilization of carbon surface is demanded in various application fields because it makes possible to employ aqueous/polar solvents as reaction and/or dispersion media. Chemical modifications of the carbon surface have been applied in previous hydrophilization techniques, whereas alternative hydrophilization pathway free from the surface modifications is expected to give considerable advantage because the obtained carbons keep inherent surface properties. Herein, we demonstrate structure-directed hydrophilization of mesoporous carbon (MC) films with well-designed mesotextures. MC films were prepared via organic-organic self-assembly of a phenolic resin in the presence of poly(styrene)-b-poly(4-vinylpyridine) and pore swelling agents. 1,3,5-Trimethylbenzene and polystyrene were employed as the pore swelling agents to control the mesotextures. Dewetting upon coating was kinetically suppressed by using solvents with a relatively low boiling point, which allows us to deposit MC films on various types of substrates. The obtained MC films exhibit a water contact angle below 30° when 1,4-dioxane and toluene are employed as coating solvents. Carbon flakes obtained from the resultant carbon films show good dispersivity in water to yield a homogenous aqueous dispersion.