Conductive PDA@HNT/rGO/PDMS aerogel composites with significantly enhanced durability and stretchability for wearable electronics

Abstract

Conductive polymer composites used to develop stretchable strain sensors have great potential for a wide range of applications, but engineering such a sensor with high sensitivity and durability remains very challenging. In this study, we propose a hydrothermal approach coupled with a freeze-drying technique to fabricate durable and stretchable strain sensors based on polydopamine-functionalized halloysite nanotube/reduced graphene oxide/polydimethylsiloxane (PDA@HNT/rGO/PDMS) aerogel composites. These sensors exhibit exceptional sensing performance, enhanced stretchability, linearity range, and stability. A comparative analysis of graphene oxide at different concentrations demonstrates that the flexible PDA@HNT/rGO/PDMS composites exhibit a significantly broader sensing range when the graphene oxide concentration is reduced to 2.5 mg/mL, in contrast to the higher concentration of 5.0 mg/mL. Specifically, the synergistic effect of both PDA and natural fiber HNTs results in aerogel composite strain sensors with a desirable gauge factor and a linearity sensing range as evidenced by the theoretical analysis, which demonstrates great potential for wearable electronics and human motion detection. The synergy between PDA and HNTs enhances the properties of aerogel composite strain sensors by improving interfacial adhesion, uniformly dispersing reinforcing agents, and maintaining conductive pathways, resulting in a highly sensitive, broad-range, and durable device. The development of conductive PDA@HNT/rGO/PDMS aerogel composites for flexible strain sensors represents an important advancement in the field of wearable technology and has the potential to revolutionize the way we monitor and respond to mechanical stress in various applications.

Keywords

Nanocomposites / polymer-matrix composites (PMCs) / finite element analysis (FEA) / natural fiber HNT

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