Topologically structured sensors with high linearity and dual-sensing signal decoupling

Abstract

Multifunctional flexible sensors capable of detecting strain, humidity, and temperature are crucial for the accurate, stable, and safe transmission of information between individuals and objects in complex environments. However, achieving multiple stimulus-response sensors with good decoupling capability remains an enormous challenge. We introduce a topological structure sensor comprising polyurethane (PU) and ionic liquids (ILs), capable of simultaneously detecting strain, temperature, and humidity. The notable feature of perfectly decoupled signals is achieved by fine-tuning the topological structure. The square-grid PU/ILs/waterborne PU (WPU) sensor demonstrates exceptional strain-sensing linearity (0.997), high temperature-sensing linearity (0.994), and superior humidity linearity (0.998), giving it dual-sensing decoupling capabilities. Additionally, the effect of the topology structure on sensing signal linearity is revealed. This research paves the way for self-decoupled multifunctional flexible sensors and their applications in human movement and respiration monitoring, as well as human–machine interaction.