Multi-functional and flexible helical fiber sensor for micro-deformation detection, temperature sensing and ammonia gas monitoring

Abstract

Flexible and wearable strain sensors with multi-functionalities have aroused tremendous attention for various applications in disease diagnostics, environment detection and healthcare monitoring, etc. However, limited electromechanical performance and complicated fabrication process of strain sensors restrict their extensive applications in full-range stimuli monitoring. Herein, we fabricated flexible and wearable strain sensors, consisting of a robust fiber with helical structure and two polyaniline (PANI) layers bridged by reduced graphene oxide (rGO) layer through in-situ polymerization and ultrasonication. The flexible and wearable sensor possesses wide healthcare monitoring range (0.1%–200% strain), high sensibility especially for subtle deformation, excellent response stability, fast response/recovery time (100 ms/100 ms) and favorable durability. Meanwhile, our conductive PANI-rGO-PANI fiber (CPGPF) is assembled as a wearable sensor with the capability of precisely monitoring human body motions, temperature fluctuation and poisonous gas, indicating a promising multifunctional application in human-machine interaction and environment monitoring.