Wei Peiqi, Guo Xiaoliang, Qiu Xianbo, Yu Duli
College of Information Science and Technology, Beijing University of Chemical Technology, 100029 Beijing, People's Republic of China.
Nanotechnology. 2019 Nov 8;30(45):455501. doi: 10.1088/1361-6528/ab3695. Epub 2019 Jul 29.
In recent years, the development of electronic skin and smart wearable body sensors has put forward high requirements for flexible pressure sensors with high sensitivity and large linear measuring range. However, it turns out to be difficult to increase both of them simultaneously. In this paper, a flexible capacitive pressure sensor based on a porous carbon conductive paste-polydimethylsiloxane composite is reported, the sensitivity and the linear measuring range of which were developed using multiple methods including adjusting the stiffness of the dielectric layer material, fabricating a microstructure and increasing the dielectric permittivity of the dielectric layer. The capacitive pressure sensor reported here has a relatively high sensitivity of 1.1 kPa and a large linear measuring range of 10 kPa, making the product of the sensitivity and linear measuring range 11, which is higher than that of the most reported capacitive pressure sensors to our best knowledge. The sensor has a detection of limit of 4 Pa, response time of 60 ms and great stability. Some potential applications of the sensor were demonstrated, such as arterial pulse wave measuring and breath measuring, which shows it as a promising candidate for wearable biomedical devices. In addition, a pressure sensor array based on the material was also fabricated and it could identify objects in the shape of different letters clearly, which shows promising application in future electronic skins.
近年来，电子皮肤和智能可穿戴人体传感器的发展对具有高灵敏度和大线性测量范围的柔性压力传感器提出了很高的要求。然而，事实证明要同时提高这两者是很困难的。本文报道了一种基于多孔碳导电膏 - 聚二甲基硅氧烷复合材料的柔性电容式压力传感器，其灵敏度和线性测量范围是通过多种方法开发的，包括调整介电层材料的刚度、制造微结构以及提高介电层的介电常数。这里报道的电容式压力传感器具有相对较高的灵敏度，为1.1 kPa，以及10 kPa的大线性测量范围，灵敏度与线性测量范围的乘积为11，据我们所知，这高于大多数已报道的电容式压力传感器。该传感器的检测极限为4 Pa，响应时间为60 ms，并且具有很好的稳定性。展示了该传感器的一些潜在应用，如动脉脉搏波测量和呼吸测量，这表明它是可穿戴生物医学设备的一个有前途的候选者。此外，还制造了基于该材料的压力传感器阵列，它可以清晰地识别不同字母形状的物体，这表明其在未来电子皮肤中具有广阔的应用前景。
