ZIF-67-incorporated multifunctional nanocomposite organohydrogel for wearable pressure and temperature sensing applications
Md. Sazzadur Rahman, Kartikeya Dixit, M. Toyabur Rahman, Keekyoung Kim, Seonghwan Kim
Abstract
Pressure and temperature are vital physiological parameters for human health assessment and monitoring, which provide essential insights into critical functions and overall well-being. Pressure sensing aids in tracking cardiovascular health and physical activity, while temperature monitoring helps detect fever, inflammation, and other health anomalies. However, achieving efficient and reliable pressure and temperature measurements with robust physical properties for healthcare applications remains challenging. Herein, we demonstrate a multifunctional, high-performance nanocomposite organohydrogel synthesized by incorporating zeolitic imidazolate framework-67 (ZIF-67) into a poly(acrylamide)–co-hydroxyethyl acrylate polymer network. The nanocomposite organohydrogel is synthesized via a one-step free-radical polymerization using a binary solvent system of water, glycerol, and choline chloride to enhance environmental stability and thermal resilience. The resulting nanocomposite organohydrogel exhibits remarkable stretchability, high toughness, strong adhesion to different substrates, and rapid self-healing within 10 s. Furthermore, it demonstrates excellent stability across a broad temperature range from − 80 to 80 °C. The low stiffness, high dielectric constant, and temperature-dependent ionic conductivity of the ZIF-67-reinforced organohydrogel enable effective detection of external stimuli. It achieves capacitive pressure sensitivity of 0.75 kPa −1 and reliable thermosensitivity with a temperature coefficient of resistance of 1.1 %/°C, demonstrating exceptional performance under dynamic conditions. Integrating advanced properties and sensing functionalities, this work presents a flexible, multifunctional wearable material designed for gait analysis and temperature monitoring, offering potential applications in healthcare and sports science.