A rigid–soft hybrid paper-based flexible pressure sensor with an ultrawide working range and frequency bandwidth

Abstract

The demand for flexible pressure sensors with high performance is increasing with the growing wearable technology market. According to the developing requirement for green electronics, paper-based sensors, which are more environmentally friendly, have received more and more attention. However, the intrinsic mechanical properties of paper materials limit the sensing performance of paper-based sensors, such as restricted working range and response bandwidth. Herein, a rigid–soft hybrid design strategy is proposed to improve the sensing performance of paper-based pressure sensors, and bioinspired microstructures are introduced into the architecture of sensors for further improvement. As a result, the prepared paper-based pressure sensor has a faster response/recovery speed (<50 ms), a wide sensing range (1 MPa) and frequency response bandwidth (0.05–1000 Hz) and excellent cycling stability (5000 cycles). In addition, the paper-based pressure sensor is superhydrophobic with a water contact angle of 152.62°. Based on the excellent sensing performance and waterproofness, the paper-based pressure sensor can be used as a wearable device for detecting joint movements or gait of humans/robots in both air and underwater. In addition, it can be used to send communication signals, showing great potential for applications in future underwater rescue.