A Novel Class of Soft Materials for Neuromorphic Electronics and Wearables: From Conducting Hydrogel to Semiconducting Hydrogel

Thin-film semiconductor-based devices have revolutionized the field of microelectronics. In the realm of biomedical applications, conducting hydrogels have rapidly gained prominence due to their mechanical and biocompatible nature with biological systems. The realization of semiconducting hydrogel materials holds significant value within the field of bioelectronics [1]. Advancing towards flexible and stretchable semiconducting hydrogels can enable direct applications at the interface of soft biological systems [1].<br/><br/>However, the development of semiconducting hydrogels presents challenges, primarily due to the thin-film nature of semiconductors, which are generally less than 1 micrometer in thickness. In contrast, hydrogels tend to have thicker thicknesses and struggle to achieve good semiconductor properties.<br/><br/>The advent of organic electrochemical transistors (OECTs) has introduced a new paradigm that can be a powerful testbed to evaluate the performance of a semiconducting hydrogel. In this report, we present the development of the PEDOT:PSS semiconducting hydrogel and its application in the development of OECTs. Furthermore, we delve into the development of stretchable semiconducting hydrogels and explore how they can revolutionize applications in the field of biomedical research.