The Platform to Characterizing the Thermoelectric Materials by Photo‐Crosslinked Ionic Gel Electrolyte

Abstract Advances in semiconductor processing have enabled the miniaturization and reduction of power consumption of devices, positioning organic thermoelectric devices—which generate electricity from any heat source—as a promising solution for self‐powered microelectronics. To make off‐grid electronics more practical, innovative thermoelectric materials with high performance need to be developed, leveraging artificial intelligence and materials informatics. This study introduces a device platform featuring a photo‐crosslinked ionic gel capable of evaluating and screening a wide range of thermoelectric material candidates with high potential. By enabling doping levels from shallow to deep, the platform provides rapid feedback for researchers. Ionic liquids, with their extensive range of oxidation and reduction capabilities, minimize the effort required to identify dopants compatible with semiconductors. During redox reactions within the ionic liquid, the platform allows continuous monitoring of changes in thermoelectric properties, optical characteristics, and crystalline structure—all within a single device. Furthermore, adjusting the ionic liquid concentration in the gel stabilizes the redox state of thermoelectric materials. The thermoelectric properties measured using this platform closely align with those achieved via chemical doping, demonstrating its potential to significantly reduce fabrication and measurement costs and time. This approach accelerates the discovery of high‐performance organic thermoelectric materials through materials informatics.