Multifunctional Hydrogel Sensor with Curved Macro Cracks: A Strategy for High Sensitivity and Wide Detection Range
Multifunctional Hydrogel Sensor with Curved Macro Cracks: A Strategy for High Sensitivity and Wide Detection Range
复制标题
弯曲型宏观裂纹多功能水凝胶传感器：一种高灵敏度、宽检测范围的策略
DOI：
10.1002/adfm.202306820
复制
发表时间：
2023-08
影响因子：
19
通讯作者：
Yu-chen Guo;Haoyu Guo;Yuwei Han;Xi Chen;Jinyuan Liu;Meng Yang;Tongqing Lu;Junrong Luo
中科院分区：
文献类型：
--
作者：
Yu-chen Guo;Haoyu Guo;Yuwei Han;Xi Chen;Jinyuan Liu;Meng Yang;Tongqing Lu;Junrong Luo
简单设备中的多传感，但具有高灵敏度和大检测范围，是软机器的理想选择。基于本体离子水凝胶电阻变化的可拉伸传感器本质上受到功能单一和小变形时灵敏度低的限制。在这里，提出了一种由高度破裂的水凝胶（HCHG）实现的设计，该水凝胶对拉伸应变、弯曲和触觉力在很宽的范围内超敏感。该机制依赖于当预切弯曲裂纹通过外部载荷闭合/打开时流动离子电流的横截面积的连续急剧变化。水凝胶的高断裂韧性抑制了裂纹扩展，使得传感稳健。通过设计裂纹图案，实现了0-20%拉伸应变的灵敏度为80，触觉力的灵敏度为0.45 kPa-1。与本体水凝胶制成的传感器相比，灵敏度分别提高了两个和三个数量级，同时保持了可检测的应变范围（高达215%）。还开发了夹层设计以区分伸长、压缩和弯曲。HCHG传感器的应用在操纵机械臂和无损抓取一个更软的物体由软夹持器演示。
Multi‐sensing in simple devices, but with a high sensitivity and a large detection range, is desirable for soft machines. Stretchable sensors based on the resistance changes of bulk ionic hydrogels are inherently limited by the single function and low sensitivity at small deformations. Here, a design enabled by a highly cracked hydrogel (HCHG) that is hypersensitive to tensile strain, bending, and tactile force in a wide range is proposed. The mechanism relies on the continuous sharp changes of the cross‐sectional area flowing ionic current when pre‐cut curved cracks are closed/opened by external load. The high fracture toughness of the hydrogel inhibits the crack propagation, making the sensing robust. By designing the crack patterns, sensitivities of 80 for 0–20% tensile strain and 0.45 kPa−1 for tactile force are achieved. Compared to the sensor made from bulk hydrogel, the sensitivities are enhanced by two and three orders of magnitude, respectively, meanwhile the detectable strain range is maintained (up to 215%). A sandwich design is also developed to distinguish elongation, compression, and bending. Applications of HCHG sensors in manipulating a robotic arm and nondestructive grasping an even softer object by a soft gripper are demonstrated.