Highly linear and low hysteresis porous strain sensor for wearable electronic skins

Poor linearity and high hysteresis as two crucial issues of stretchable and flexible strain sensors are urgently needed to be addressed to improve the sensors' practical applicability. In this work, sacrificial template method coupled with ultrasonication technique are employed to fabricate a carbon black (CB)/polydimethylsiloxane (PDMS) foam (CPF) for tensile sensing. The CPF with a robust three-dimensional (3D) electrically conductive network exhibits excellent linearity and wide strain range (70% strain). The fabricated CPF possesses negligible electrical hysteresis of 1.2%, owing to the strong interactions between conductive nanofillers and the PDMS substrate. Low detection limit (0.5% strain), quick responsive time (100 ms), good response stability, excellent durability and reproducibility (>20,100 cycles) are achieved simultaneously. The prepared CPF is then assembled as a wearable sensor and it can monitor wide-range human motions in real-time, showing great potential in diverse practical applications in the near future.

Automated summary

In this study, a stretchable and flexible strain sensor with excellent linearity and wide strain range was fabricated using sacrificial template method and ultrasonication technique. The sensor exhibited minimal electrical hysteresis, low detection limit, quick responsive time, good response stability, excellent durability, and reproducibility. Assembled as a wearable sensor, it can monitor a wide range of human motions in real-time, showing great potential for diverse practical applications in the future.