(178r) Liquid Metal Crosslinked Poly(3,4-ethylenedioxythiophene) Polystyrene Sulfonate (PEDOT: PSS) Conductive and Injectable Hydrogel

Conductive hydrogels play an important role in biointerfaces, bioelectronics, and medical applications due to their excellent properties. In recent years, the conductive polymer composite poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT: PSS) has emerged as a potential material for conductive hydrogels. However, the preparation method of PEDOT:PSS hydrogel is complicated and its strength is insufficient, which limits its application in bioelectronics. Gallium-based liquid metals show promising properties in the field of soft bioelectronics. Therefore, our recent work developed a simple synthesis method for PEDOT:PSS hydrogels based on liquid metal eutectic gallium indium (EGaIn). We use sonication to break down EGaIn into uniform nanoparticles and then cross-link the PEDOT:PSS polymer into a conductive hydrogel. We propose two different cross-linking mechanisms. The results showed that EGaIn greatly improved the strength of the hydrogel, which was related to the release of gallium ions. And due to the injectable properties of hydrogels, we successfully printed hydrogels, which have great potential in patterning hydrogels and preparing organic electrochemical transistors (OECTs).