Lee Su Yeon, Rahmawan Yudi, Yang Shu
Department of Materials Science and Engineerng, University of Pennsylvania , 3231 Walnut Street, Philadelphia, Pennsylvania 19104, United States.
ACS Appl Mater Interfaces. 2015 Nov 4;7(43):24197-203. doi: 10.1021/acsami.5b07551. Epub 2015 Oct 16.
Transparent, superamphiphobic surfaces that repel both water and oils are prepared from mushroom-like micropillar arrays consisting of nanoparticles only at the top of the pillars by controlled compartment filling of silica nanoparticles into the bottom of the poly(dimethylsiloxane) (PDMS) mold, followed by infiltration of epoxy and UV curing. Because silica nanoparticle decorated pillar heads are more resistant to O2 plasma than the polymer pillars, we can precisely control the head size of micropillars and nanoroughness on top of the pillar heads by varying the O2 plasma time. The combination of nanoroughness and mushroom-like micropillars leads to superhydrophobicity and oil repellency to different organic solvents. High transparency is achieved by increasing the spacing ratio of micropillars. Last, we demonstrate anisotropic wetting on the hierarchical surface can be achieved by combining photolithography, replica molding, and self-assembly techniques.
通过将二氧化硅纳米颗粒可控地填充到聚二甲基硅氧烷（PDMS）模具底部，随后进行环氧树脂浸润和紫外线固化，由仅在柱顶由纳米颗粒组成的蘑菇状微柱阵列制备出既拒水又拒油的透明超双疏表面。由于用二氧化硅纳米颗粒修饰的柱头比聚合物柱对氧气等离子体更具抗性，我们可以通过改变氧气等离子体处理时间来精确控制微柱的头部尺寸以及柱头顶部的纳米粗糙度。纳米粗糙度与蘑菇状微柱的结合导致对不同有机溶剂具有超疏水性和拒油性。通过增加微柱的间距比可实现高透明度。最后，我们证明通过结合光刻、复制成型和自组装技术，可以在分级表面上实现各向异性润湿。
