Coaxial-helix MXene/PANI-based core-spun yarn towards strain-insensitive conductor and supercapacitor

Stretchable electrical conductors hold great promise in the wearable electronic devices, such as flexible display and human-machine interface. Stable conductivity is vital for wearable devices to maintain their stable performance. However, the electrical resistance of most reported yarns dramatically increases when they are deformed. Herein, we propose a design for a coaxial-helix structure by wrapping the polyaniline/MXene-based elastic core-spun yarn on itself in the form of coils. The fabricated coaxial-helix structured yarns (DCSs) exhibit excellent strain-insensitive properties, including low relative resistance change (25.4%), large strain (200%) and high quality factor (17.95). Moreover, the DCSs can be used as the stretchable electrodes for the supercapacitors, and delivers a linear specific capacitance of 256.7 mF cm−1, which is higher than most stretchable yarns. Therefore, the proposed coaxial-helix structure design creates a new approach for the strain-insensitive stretchable conductor, thereby paving the way for the development of stretchy electronics.