Biomimetic coating-free surfaces for long-term entrapment of air under wetting liquids.

ABSTRACT: Trapping air at the solid-liquid interface is a promising strategy for reducing frictional drag and desalting water, although it has thus far remained unachievable without perfluorinated coatings. Here, we report on biomimetic microtextures composed of doubly reentrant cavities (DRCs) and reentrant cavities (RCs) that can enable even intrinsically wetting materials to entrap air for long periods upon immersion in liquids. Using SiO₂/Si wafers as the model system, we demonstrate that while the air entrapped in simple cylindrical cavities immersed in hexadecane is lost after 0.2 s, the air entrapped in the DRCs remained intact even after 27 days (~10⁶ s). To understand the factors and mechanisms underlying this ten-million-fold enhancement, we compared the behaviors of

SUBMITTER: Domingues EM 

PROVIDER: S-EPMC6127334 | biostudies-literature | 2018 Sep

REPOSITORIES: biostudies-literature