Tang Guijun, Yin Keke, Xing Zhiwen, Liu Yanyan, Ten Elshof Johan E, Shan Chongxin, Li Baojun, Yuan Huiyu
Henan Key Laboratory of High Temperature Functional Ceramics, School of Materials Science and Engineering, Zhengzhou University, Zhengzhou 450001, P.R. China.
Henan Institute of Product Quality Supervision and Inspection, Zhengzhou 450047, China.
ACS Appl Mater Interfaces. 2024 Oct 2. doi: 10.1021/acsami.4c10559.
Flexible pressure sensors present enormous potential for applications in health monitoring, human-machine interfacing, and electronic skins (e-skin). However, at the cost of flexibility, the design of flexible pressure sensors has been facing the trade off between high sensitivity and wide sensing range. Herein, we propose a sandwiched structure composed of monolayer films of calcium niobate nanosheets to endow the device with both ultrahigh sensitivity and a wide sensing range. Tunable contact between the two electrodes of the pressure sensor through the gaps in the insulative monolayer film and precise thickness modulation of the monolayer films at the nanoscale result in an ultrahigh sensitivity and wide sensing range of the sensors. By virtue of these two traits, the pressure sensor distinguishes itself with unprecedented performances of ultrahigh sensitivity (6.43 × 10 kPa), a wide sensing range (1.94-60.00 kPa), a fast response time (<165 ms), and reliable repeatability. In addition, the sensor has a sensing mechanism transition from capacitive mode to piezoresistive mode from low pressure to high pressure. The sensors demonstrates the ability for motion detection of the human body. This work sheds light on the development of highly sensitive flexible pressure sensors.
柔性压力传感器在健康监测、人机交互和电子皮肤（e-skin）等应用中具有巨大潜力。然而，以牺牲柔韧性为代价，柔性压力传感器的设计一直面临着高灵敏度和宽传感范围之间的权衡。在此，我们提出一种由铌酸钙纳米片单层膜组成的夹心结构，以使器件兼具超高灵敏度和宽传感范围。通过绝缘单层膜中的间隙实现压力传感器两个电极之间的可调接触，以及在纳米尺度上对单层膜进行精确的厚度调制，从而实现了传感器的超高灵敏度和宽传感范围。凭借这两个特性，该压力传感器具有超高灵敏度（6.43×10 kPa）、宽传感范围（1.94 - 60.00 kPa）、快速响应时间（<165 ms）和可靠的重复性等前所未有的性能。此外，该传感器具有从低压到高压从电容模式到压阻模式的传感机制转变。这些传感器展示了对人体运动进行检测的能力。这项工作为高灵敏度柔性压力传感器的发展提供了启示。
