| 초록 |
Springtails possess robust omniphobic skins with nanotextures with a doubly re-entrant geometry(DRG). Although omniphobic surfaces are promising for various applications, it remains an important challenge to mimic the structural feature of springtails. This paper presents a pragmatic method to create DRG and robust super-omniphobic surfaces by exploiting localized photofluidization of azopolymers. Irradiation of circularly-polarized light reconfigures azopolymer micropillars to have a mushroom-like head with a DRG through protrusion and inward bending of polymer film from the top edge. The geometry exhibits super-omniphobicity even for liquids whose equilibrium contact angles are almost zero in the presence of a practical level of external pressure. The simple fabrication process is highly reproducible, scalable, and compatible with various substrates. Our results suggest that our photofluidization technology will provide a practical route to create robust super-omniphobic surfaces. |
