Nanoprobe Laboratory for Bio- & Nanotechnology and Biomimetics, The Ohio State University, Columbus, OH 43210, USA.
J Colloid Interface Sci. 2012 Apr 15;372(1):231-8. doi: 10.1016/j.jcis.2012.01.020. Epub 2012 Jan 16.
The mechanics of fibrillar adhesive surfaces of biological systems such as a Lotus leaf and a gecko are widely studied due to their unique surface properties. The Lotus leaf is a model for superhydrophobic surfaces, self-cleaning properties, and low adhesion. Gecko feet have high adhesion due to the high micro/nanofibrillar hierarchical structures. A nanostructured surface may exhibit low adhesion or high adhesion depending upon fibrillar density, and it presents the possibility of realizing eco-friendly surface structures with desirable adhesion. The current research, for the first time uses a patterning technique to fabricate smart adhesion surfaces: single- and two-level hierarchical synthetic adhesive structure surfaces with various fibrillar densities and diameters that allows the observation of either the Lotus or gecko adhesion effects. Contact angles of the fabricated structured samples were measured to characterize their wettability, and contamination experiments were performed to study for self-cleaning ability. A conventional and a glass ball attached to an atomic force microscope (AFM) tip were used to obtain the adhesive forces via force-distance curves to study scale effect. A further increase of the adhesive forces on the samples was achieved by applying an adhesive to the surfaces.
由于其独特的表面特性，生物系统（如荷叶和壁虎）的纤维状粘性表面的力学性能被广泛研究。荷叶是超疏水表面、自清洁特性和低粘附性的模型。壁虎的脚具有高附着力，这是由于其具有高度的微/纳纤维状分层结构。纳米结构表面的附着力可能较低或较高，这取决于纤维密度，并为实现具有理想附着力的环保表面结构提供了可能性。本研究首次使用图案化技术来制造智能粘附表面：具有不同纤维密度和直径的单级和两级分层合成的粘附结构表面，可以观察到荷叶或壁虎的粘附效果。通过测量所制备的结构化样品的接触角来表征其润湿性，并进行污染实验来研究自清洁能力。使用原子力显微镜（AFM）尖端上的常规和玻璃球来通过力-距离曲线获得粘附力，以研究比例效应。通过在表面施加粘附剂，进一步提高了样品上的粘附力。
