Due to their low-temperature solution processability, compatibility with large-area deposition techniques, intrinsic robust mechanical properties and excellent light-emitting properties, organic polymer semiconductors possess great potential as functional thin-film devices, such as field effect transistors, thermoelectric energy conversion devices and light-emitting devices. Because of these unique advantages, organic polymer films are extremely suitable for future IoT technology and large-area high-performance devices are highly required. However, in most functional devices, fine tuning of carrier concentration is key technique and, still, it is very difficult for organic polymer films to control their carrier density precisely.
Recently, we combined electrochemical doping technique with functional devices of several materials and we successfully maximized their device performance [1-8]. Here, we applied these techniques into organic polymer films and realized unique functionalities, i) insulator-to-metal transition induced by electrochemical doping, ii) electrochemically optimized thermoelectric energy conversion efficiency in organic polymer films and iii) highly functionalized light-emitting electrochemical cells based on organic polymers.
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