Flexible pressure sensor with wide pressure range based on 3D microporous PDMS/MWCNTs for human motion detection

Abstract

Introducing microstructure in the flexible pressure sensors is an effective strategy to enhance the performance of the sensor. Herein, we fabricated a flexible pressure sensor with three-dimensional (3D) miroporous based on a hybrid of polydimethylsiloxane (PDMS) and multiwalled carbon nanotubes (MWCNTs). The 3D microporous was produced by a facile and low-cost process using NH₄HCO₃ as a sacrificial template, the NH₄HCO₃ particles were decomposed to gas and left microporous in the hybrid of PDMS and MWCNTs. The microporous structure inside the sensor allowed for a wide pressure range (∼140 kPa). The sensor could detect large motions of finger, wrist, elbow, knee, and even small motion such as facial expression. In addition, a 3 × 3 tactile sensor array was successfully applied in the pressure distribution of fingers to grasp a cup. The results demonstrate that the sensor is promising application in wearable electronics and human-machine interfaces for pressure sensing.