N-Type Semiconducting Hydrogel

Hydrogels are an attractive category of biointerfacing materials with adjustable mechanical properties, diverse biochemical functions, and good ionic conductivity. Despite these advantages, their application in electronics has been restricted due to their lack of semiconducting properties, as they have traditionally only served as insulators or conductors. We develop single and multiple network hydrogels based on a water-soluble n-type semiconducting polymer, thereby endowing conventional hydrogels with semiconducting capabilities. These hydrogels show good electron mobilities and high on/off ratios, enabling the fabrication of complementary logic circuits and signal amplifiers with low power consumption and high gains. We demonstrate that hydrogel electronics can sense and amplify electrophysiological signals with enhanced signal-to-noise ratios. Our work could enable more optoelectronic properties and greatly expand the applications of hydrogels in bioelectronics.