Smooth, transparent and nonperfluorinated surfaces exhibiting unusual contact angle behavior toward organic liquids

Smooth, transparent and nonperfluorinated surfaces exhibiting unusual contact angle (CA) behavior toward various organic liquids have been prepared using a simple sol–gel solution containing decyltriethoxysilane (DTES) and tetramethoxysilane (TMOS). The insertion of co-condensed silica units derived from TMOS as a spacer between the neighboring alkyl (decyl) chains allows them to rotate freely and provide a surface with liquid-like properties. The resulting surfaces exhibit negligible CA hysteresis for probe liquids, allowing the droplets to move easily and roll off when only slightly tilted, without relying on conventional surface roughening and perfluorination.