Institute of Semiconductors, Chinese Academy of Sciences, Beijing 100083, China.
College of Materials Science and Opto-Electronic Technology, University of Chinese Academy of Sciences, Beijing 100049, China.
ACS Appl Mater Interfaces. 2024 Feb 14;16(6):7640-7649. doi: 10.1021/acsami.3c18788. Epub 2024 Feb 1.
High-performance flexible piezoresistive sensors are becoming increasingly essential in various novel applications such as health monitoring, soft robotics, and human-computer interaction. The evolution of the interfacial contact morphology determines the sensing properties of piezoresistive devices. The introduction of microstructures enriches the interfacial contact morphology and effectively boosts the sensitivity; however, the limited compressibility of conventional microstructures leads to rapid saturation of the sensitivity in the low-pressure range, which hinders their application. Herein, we present a flexible piezoresistive sensor featuring a two-stage micropyramid array structure, which effectively enhances the sensitivity while widening the sensing range. Owing to the synergistic enhancement effect resulting from the sequential contact of micropyramids of various heights, the devices demonstrate remarkable performance, including boosting sensitivity (30.8 kPa) over a wide sensing range (up to 200 kPa), a fast response/recovery time (75/50 ms), and an ultralong durability of 15,000 loading-unloading cycles. As a proof of concept, the sensor is applied to detect human physiological and motion signals, further demonstrating a real-time spatial pressure distribution sensing system and a game control system, showing great potential for applications in health monitoring and human-computer interaction.
高性能柔性压阻传感器在健康监测、软机器人和人机交互等各种新型应用中变得越来越重要。界面接触形态的演变决定了压阻器件的传感性能。微结构的引入丰富了界面接触形态，有效地提高了灵敏度；然而，传统微结构的压缩能力有限，导致在低压范围的灵敏度迅速饱和，限制了其应用。在此，我们提出了一种具有两级微金字塔阵列结构的柔性压阻传感器，有效地提高了灵敏度，同时拓宽了传感范围。由于不同高度的微金字塔的顺序接触产生的协同增强效应，这些器件表现出显著的性能，包括在宽传感范围内（高达 200kPa）提高灵敏度（30.8kPa），快速的响应/恢复时间（75/50ms），以及超过 15000 次加载-卸载循环的超长耐用性。作为概念验证，该传感器被应用于检测人体生理和运动信号，进一步展示了实时空间压力分布传感系统和游戏控制系统，在健康监测和人机交互应用中具有很大的潜力。
