School of Mechanical Engineering, Nanjing University of Science and Technology, Nanjing 210094, China.
School of Mechanical Engineering, Nanjing University of Science and Technology, Nanjing 210094, China.
Adv Colloid Interface Sci. 2023 Mar;313:102862. doi: 10.1016/j.cis.2023.102862. Epub 2023 Feb 20.
In nature, millions of creatures, such as geckos, tree frogs, octopuses, etc., have evolved fantastic switchable adhesion capabilities to climb swiftly on vertical even inverted surfaces or hunt for prey easily, adapting to harsh and unpredictable environments. Notably, these fascinating adhesive behaviors depend on interfacial forces (friction, van der Waals force, capillary force, vacuum suction, etc.), which primarily originate from the interactions between the soft micro/nanostructures evolved in the natural creatures and objects. Over the past few decades, these biological switchable adhesives have inspired scientists to explore and engineer desirable artificial adhesives. In this review, we summarized the state-of-the-art research on the ultra-fast adhesive motion of three types of biological organisms (gecko, tree frog, and octopus). Firstly, the basic adhesion principles in the three representative organisms, including micro/nanostructures, interfacial forces, and fundamental adhesion models, are reviewed. Then, we discussed the adhesion mechanisms of the prominent organisms from the perspective of soft contacts between micro/nanostructures and the substrates. Later, the mechanics-guided design principles of artificial adhesive surfaces, as well as the smart adhesion strategies, are summarized. The applications of these bio-inspired switchable adhesives are demonstrated, including wearable electronic devices, soft grippers, and climbing robots. The challenges and opportunities in this fast-growing field are also discussed.
在自然界中，数以百万计的生物，如壁虎、树蛙、章鱼等，已经进化出了奇妙的可切换的粘附能力，可以在垂直甚至倒置的表面上迅速攀爬，或者轻松地捕食猎物，从而适应恶劣和不可预测的环境。值得注意的是，这些引人入胜的粘附行为依赖于界面力（摩擦力、范德华力、毛细作用力、真空吸力等），这些界面力主要源于自然生物和物体中进化出的软微纳结构之间的相互作用。在过去的几十年中，这些生物可切换的粘合剂激发了科学家探索和设计理想的人工粘合剂。在这篇综述中，我们总结了三种生物（壁虎、树蛙和章鱼）的超快速粘附运动的最新研究进展。首先，我们回顾了这三种代表性生物中的基本粘附原理，包括微纳结构、界面力和基本粘附模型。然后，我们从微纳结构与基底之间的软接触的角度讨论了突出生物的粘附机制。之后，总结了人造粘附表面的力学指导设计原则和智能粘附策略。展示了这些受生物启发的可切换粘合剂的应用，包括可穿戴电子设备、软夹爪和攀爬机器人。还讨论了这个快速发展领域的挑战和机遇。
