School of Materials Science and Engineering, Sun Yat-sen University, 135 Xingang Road West, Guangzhou 510275, China.
J Mater Chem B. 2020 Apr 29;8(16):3437-3459. doi: 10.1039/c9tb02570g.
Flexible pressure and strain sensors have great potential for applications in wearable and implantable devices, soft robotics and artificial skin. Compared to flexible sensors based on filler/elastomer composites, conductive hydrogels are advantageous due to their biomimetic structures and properties, as well as biocompatibility. Numerous chemical and structural designs provide unlimited opportunities to tune the properties and performance of conductive hydrogels to match various demands for practical applications. Many electronically and ionically conductive hydrogels have been developed to fabricate pressure and strain sensors with different configurations, including resistance type and capacitance type. The sensitivity, reliability and stability of hydrogel sensors are dependent on their network structures and mechanical properties. This review focuses on tough conductive hydrogels for flexible sensors. Representative strategies to prepare stretchable, strong, tough and self-healing hydrogels are briefly reviewed since these strategies are illuminating for the development of tough conductive hydrogels. Then, a general account on various conductive hydrogels is presented and discussed. Recent advances in tough conductive hydrogels with well designed network structures and their sensory performance are discussed in detail. A series of conductive hydrogel sensors and their application in wearable devices are reviewed. Some perspectives on flexible conductive hydrogel sensors and their applications are presented at the end.
柔性压力和应变传感器在可穿戴和植入式设备、软机器人和人造皮肤等领域具有巨大的应用潜力。与基于填充剂/弹性体复合材料的柔性传感器相比，导电水凝胶具有仿生结构和性能以及生物相容性等优点。许多化学和结构设计为调节导电水凝胶的性能和性能提供了无限的机会，以满足各种实际应用的需求。已经开发出许多电子和离子导电水凝胶来制造具有不同配置的压力和应变传感器，包括电阻型和电容型。水凝胶传感器的灵敏度、可靠性和稳定性取决于其网络结构和机械性能。本综述重点介绍了用于柔性传感器的坚韧导电水凝胶。简要回顾了制备可拉伸、强韧和自修复水凝胶的代表性策略，因为这些策略为坚韧导电水凝胶的发展提供了启示。然后，对各种导电水凝胶进行了概述和讨论。详细讨论了具有精心设计的网络结构和良好传感性能的坚韧导电水凝胶的最新进展。综述了一系列导电水凝胶传感器及其在可穿戴设备中的应用。最后提出了对柔性导电水凝胶传感器及其应用的一些看法。
