Lab-Synthesized Pristine Poly(3,4-ethylenedioxythiophene):Poly(styrenesulfonate) Hydrogels with Low Electrical Hysteresis for Stretchable Multifunctional Electronics

The demand for smart materials has driven the development of multifunctional systems combining conductivity, stretchability, and durability. Conductive hydrogels are promising candidates for stretchable electronics and wearable devices. Herein, lab-synthesized pristine poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (L-PEDOT:PSS) hydrogels with enhanced conductivity were obtained using dimethyl sulfoxide (DMSO) doping. The hydrogels were produced via a dry-annealing and immersion method in Dulbecco’s phosphate-buffered saline (DPBS), achieving a conductivity of 75.37 S cm–1. The hydrogels exhibited multifunctional performance, including electromagnetic interference (EMI) shielding (35.54 dB), Joule heating (84.93 °C at 6 V), and strain sensing of joint bending and muscle activity. Real-time wireless motion detection further validated strain sensitivity during finger bending, mouse clicks, and pressure sensing. Optimizing the DMSO content, annealing temperature, and immersion time significantly improved the properties. These results highlight the potential of L-PEDOT:PSS hydrogels as multifunctional platforms for smart materials, wearable sensors, and EMI shielding systems.