Integrated Materials Design and Process Engineering for n-Type Polymer Thermoelectrics

Polymer thermoelectrics (TEs) have attracted increasing interest in recent years, owing to their great potential in intimate integration with wearable electronics for powering small electronics/sensors and personal temperature regulation. Over the past few decades, substantial progress has been made in enhancing polymer TE performance. However, the electrical conductivity and power factor of most n-doped polymers are about an order of magnitude lower than those of their p-type counterparts, impeding the development of highly efficient polymer TE devices. In addition, unlike well-studied inorganic materials, the complex charge transport mechanism and polymer-dopant interactions in polymer TE materials have hindered a comprehensive understanding of the structure-property relationships. This Perspective aims to survey recent achievements in understanding the charge transport mechanism and selectively provide some critical insights into molecular design and process engineering for n-type polymer TEs. We also highlight the great potential of polymer TEs in wearable electronics and offer an outlook for future development.