Superhydrophobic cotton-based piezoresistive pressure sensor for detecting human motions

Abstract

Flexible pressure sensors have attracted considerable attention due to their widely applications in healthcare monitoring and artificial intelligence. However, most of them are based on the petroleum and petroleum derivatives, leading to the increasing carbon emission and the aggravating deterioration of environment. On the other hand, it remains a challenge to explore pressure sensors that possess excellent superhydrophobicity and hence can be used in harsh environment. To solve these issues, copper nanowires functionalized cotton fibers (Cu NWs/cotton) is reported here to fabricate piezoresistive pressure sensor through a facile one-step dip-coating process. The Cu NWs coated on cotton fibers not only constructed conductive network but also decreased the surface energy by hexadecylamine capped on them, resulting excellent superhydrophobicity and the water contact angle reached 154°. Furthermore, the Cu NWs/cotton based sensor exhibited benign sensitivity (0.15 kPa −1 ), response time (400 ms), and stability (500 loading/unloading cycles). Owing to these merits, the cotton-based sensor was successfully applied for detecting human motions. The findings provide a facile and sustainable approach to fabricate superhydrophobic piezoresistive pressure sensor for flexible electronics even under humid environment. • Superhydrophobic conductive cotton fabric was fabricated by one-time dip-coating. • The stable morphology of Cu NWs/cotton was obtained by varying the dimensions of Cu NWs and the times of dip-coating cycle. • The Cu NWs/cotton showed superior conductive and superhydrophobic stabilities. • The cotton based sensor exhibited benign sensing performance and was further used to detecting human motions.