Ultrasensitive Ionic Liquid Polymer Composites with a Convex and Wrinkled Microstructure and Their Application as Wearable Pressure Sensors
Changwoo Cho, Dong‐Won Kim, Chaeeun Lee, Je Hoon Oh
Abstract
The development of pressure sensors with high sensitivity and effectiveness that exhibit linearity over a wide pressure range is crucial for wearable devices. In this study, we fabricated a novel ionic liquid (IL)/polymer composite with a convex and randomly wrinkled microstructure in a cost-effective and facile manner using an opaque glass and stretched polydimethylsiloxane template. The fabricated IL/polymer composite was used as the dielectric layer in a capacitive pressure sensor. The sensor exhibited a high linear sensitivity of 56.91 kPa –1 owing to the high interfacial capacitance formed by the electrical double layer of the IL/polymer composite over a relatively wide range (0–80 kPa). We also demonstrated the sensor performance for various applications such as a glove-attached sensor, sensor array, respiration monitoring mask, human pulse, blood pressure measurement, human motion detection, and a wide range of pressure sensing. It would be expected that the proposed pressure sensor has sufficient potential for use in wearable devices.