An integrated polyacrylonitrile fiber mat sensor for simultaneous temperature and pressure monitoring in high-temperature environments

Abstract

Flexible sensors capable of simultaneous temperature and pressure monitoring are highly desirable for electronic skin, wearable devices, and safety monitoring in high-temperature environments. However, existing flexible sensors are often limited by narrow operating temperature ranges, thermally induced signal interference, and insufficient durability under cyclic mechanical loading. This study develops a flexible wide-temperature-range temperature-pressure sensor based on polyacrylonitrile fiber mats. By combining laser processing or heat treatment, the electrical properties of polyacrylonitrile are regulated in situ, enabling its use as a multimodal sensing material. Temperature sensing is achieved through the thermosensitive effect of the treated polyacrylonitrile fiber mat, with a resolution of 0.1 °C in the temperature range of 25 °C-300 °C. Pressure sensing is realized through the piezoresistive response of polyacrylonitrile nanowires, featuring a measurement range of 0-480 kPa and response/recovery time of 53.2 ms/8.8 ms. After 10,000 loading-unloading cycles, the pressure-response attenuation remains below 1%, demonstrating good mechanical durability. Furthermore, the sensor exhibits reliable responses under dynamic thermal-mechanical coupling conditions and can be integrated with robotic grippers for simultaneous temperature and pressure perception. These results suggest that the proposed sensor holds promise for lithium-ion battery thermal management, industrial equipment condition monitoring, and emergency rescue applications in high-temperature environments.