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.