Rational Engineering of π-Conjugated Polymer/rGO/Ecoflex Hybrid Networks for Highly Sensitive and Robust Piezoresistive Sensing

Flexible and highly sensitive strain sensors are necessary for the evolution of wearable electronics, soft robotics, and human–machine interfaces. In this study, we present an in situ synthesized PAni-rGO/Ecoflex-based strain sensor that demonstrates remarkable sensitivity, stretchability, and durability. The functionalized rGO provides uniform dispersion and improved interfacial adhesion inside the Ecoflex matrix, resulting in a stable 3D conductive network. The sensor exhibits an excellent gauge factor of ∼239.1, a wide sensing range (>120%), and outstanding long-term cyclic stability. The sensing mechanism integrates tunneling conduction, microcrack evolution, and hopping transport, where PAni employs its flexible conjugated chains to bridge microcracks and maintain partial connectivity. Thermogravimetric analysis showed great stability up to 100 °C, and resistance is unaffected by moisture absorption of more than 4%, ensuring environmental resilience. These characteristics make the sensor an attractive choice for next-generation wearable electronics and multifunctional intelligent sensing systems.