Lin Jian, Zhou Peidi, Wen Zhiyuan, Zhang Wei, Luo Zhiling, Chen Luzhuo
Fujian Provincial Key Laboratory of Quantum Manipulation and New Energy Materials, College of Physics and Energy, Fujian Normal University, Fuzhou, 350117, China.
Fujian Provincial Collaborative Innovation Center for Advanced High-Field Superconducting Materials and Engineering, Fuzhou, 350117, China.
Nanoscale. 2021 Dec 13;13(47):20134-20143. doi: 10.1039/d1nr06111a.
Actuators have wide applications in soft robotics and bionic devices. Since the healing ability not only makes actuators have longer service lives, but also allows them to be programmable through welding and assembling, it is regarded as an important feature for state-of-the-art actuators. Nevertheless, it remains a great challenge to integrate multi-functional merits, such as multi-responsiveness, programmable shape-morphing, healing and self-sensing function, simultaneously into a monolithic actuating material. Here, we introduce Chinese ink, a carbon-based material used in traditional calligraphy, to develop programmable, dual-responsive and self-sensing actuators by a healing-assembling method. The ink is combined with graphene oxide (GO) to fabricate a double-layer ink/GO actuator, which shows bi-directional bending under near-infrared light or humidity, owing to the mismatch of the volume change between ink and GO films. The maximal bending curvature is up to 5.2 cm. Importantly, the entire ink/GO actuator can be healed with the aid of ink solution. Using the healing-assembling method to fabricate advanced structures including a Mobius ring, triangular rings and square rings, diverse actuating modes and complex 3D deformations such as a wavy shape and saddle shape are realized. This method also enables the construction of an artificial mimosa that shows a biomimetic stimulus-responsive behavior. In addition, the ink/GO actuator shows a self-sensing function, which is attributed to the thermoresistivity of the ink film. This research shows the huge potential of Chinese-ink-based actuators for use in smart materials, providing a new idea for the development of new generation multi-functional actuators.
致动器在软体机器人和仿生设备中有着广泛的应用。由于自愈能力不仅使致动器具有更长的使用寿命，还能通过焊接和组装实现可编程性，因此它被视为先进致动器的一项重要特性。然而，将多功能优点，如多响应性、可编程形状变形、自愈和自感应功能，同时集成到一种整体式致动材料中仍然是一个巨大的挑战。在此，我们引入中国传统书法中使用的碳基材料——墨汁，通过自愈组装法来开发可编程、双响应和自感应的致动器。墨汁与氧化石墨烯（GO）结合制成双层墨汁/GO致动器，由于墨汁和GO薄膜之间体积变化的不匹配，该致动器在近红外光或湿度作用下会发生双向弯曲。最大弯曲曲率可达5.2厘米。重要的是，整个墨汁/GO致动器可以借助墨汁溶液实现自愈。利用自愈组装法制造包括莫比乌斯环、三角环和方环在内的先进结构，实现了多种致动模式和复杂的3D变形，如波浪形和鞍形。这种方法还能构建出表现出仿生刺激响应行为的人造含羞草。此外，墨汁/GO致动器具有自感应功能，这归因于墨汁薄膜的热阻特性。这项研究展示了基于墨汁的致动器在智能材料领域的巨大应用潜力，为新一代多功能致动器的开发提供了新思路。
