Highly Stable and Temperature-Independent Humidity Sensor Based on PEO/PVA Polymer Composite

Abstract

Traditional humidity sensors frequently face challenges, especially in environments with fluctuating temperatures, which can compromise their efficiency, stability, and reliability. Therefore, there is an urgent demand to fabricate low-cost and high-performance temperature-independent humidity sensors. In this work, for the first time, highly stable and reliable temperature-independent humidity sensors have been proposed based on a PEO/PVA polymer composite. Four sensors were fabricated containing weight ratios of PEO/PVA as 50:50%, 40:60%, 60:40%, and 70:30%, respectively. All of the fabricated sensors were electrically characterized at three different temperatures, 30 °C, 35 °C, and 40 °C, to investigate the impedance response. The proposed sensor based on a PEO/PVA (40:60%) composite presents a remarkable and optimized temperature-independent performance in the range of 0–60%RH. Apart from this, the response and recovery time (9 s/16 s) of the temperature-independent humidity sensor based on PEO/PVA (40:60%) were investigated. Finally, the sensor showed long-term stability for 90 days, ensuring the reliability of the proposed device. These remarkable performances of the proposed sensor based on PEO/PVA with a weight ratio of (40:60)% can open a new gateway for low-range temperature-independent humidity sensors for various real-time applications.