Temperature-sensitive dual-matrix composite ink for ultrahigh-density and large-scale flexible temperature microsensor array

Abstract

Flexible temperature sensor arrays (FTSAs) are critical in applications such as biomedical monitoring and environmental assessment due to their capacity to capture local temperature changes. However, developing FTSAs with high sensitivity, high sensing density, and large scalability remains a daunting challenge. Herein, a novel composite ink with a dual polymer matrix that facilitates the fabrication of high-performance flexible temperature sensors is developed. Taking the advantage of screen-printing technology, flexible temperature sensors with a minimum side length of 500 μm are fabricated. Furthermore, an ultrahigh-density and large-scale FTSA with up to 2500 units (50 × 50) is developed, accompanied by a real-time data acquisition system to achieve heat source localization and thermal imaging. Within the temperature range of 25–40 °C, the sensor demonstrates the highest temperature coefficient of resistance of 14.4 %/°C, excellent resolution of 0.1 °C, superior thermal cycling stability (1000 cycles), and insensitivity to additional stimuli such as bending, humidity, pressure, and vibration, demonstrating applications in respiratory monitoring and temperature monitoring. These results provide a novel idea for temperature monitoring in applications such as pet temperature monitoring, electronic skin (e-skin) and smart skin for aircraft.