Carbon aerogel reinforced PDMS nanocomposites with controllable and hierarchical microstructures for multifunctional wearable devices

Abstract

Wearable devices have attracted increasing attention for development of personal healthcare. In this study, three-dimensional porous carbon aerogels reinforced polydimethylsiloxane nanocomposites with controllable and hierarchical open, semi-open and closed cell structures were developed for multifunctional wearable heating and sensing devices. This investigation reveals that the microstructures of the aerogels play a critical role in determining nanocomposites properties, particularly their heating and sensing performances. As thermotherapy heaters, the nanocomposite with semi-open cell structure is observed with the highest energy transduction efficiency (equilibrium temperature ∼138.9 °C under only 5 V) compared to the nanocomposites with open and closed cell structures, due to the well-defined conductive network and structural stability. As stimuli-responsive sensors, compared to the nanocomposite with closed cell structure, the nanocomposites with open and semi-open cell structures are observed with higher sensitivity (gauge factor ∼369.03) and much better repeatability, benefiting from their structural integrity. Finally, the nanocomposite with semi-open cell structure was investigated for practical potential on human body. Experimental results demonstrated the uniform temperature distribution and reliable sensitivity as a multifunctional wearable device. Therefore, by controlling and optimizing the microstructure of carbon aerogels, the nanocomposites with tailored microstructure could be exploited for various engineering applications including emerging multifunctional wearable devices.