High Performance and Colorful Polymer Thermoelectrics with Imprinted Porous Film

Abstract The rapid development of the Internet of Things and wearable electronics has generated growing interest in creating high‐performance and visually striking polymer thermoelectric (TE) devices. However, existing polymer TE materials have yet to fully meet these diverse demands. In this study, imprinted porous polymer films are introduced that exhibit both high TE performance and a spectrum of structural colors. The porous architecture not only preserves excellent charge transport properties but also significantly enhances phonon‐like scattering, resulting in a more than 50% reduction in thermal conductivity for the PDPPSe‐12 film. This leads to a 170% increase in the figure of merit (ZT), achieving a peak value of 0.52 at 363 K. Furthermore, the highly ordered porous structure imparts the PDPPSe‐12 films with both a wide range of structural colors and remarkable stretchability, making them ideal for wearable TE generators. This approach is widely applicable to various polymeric systems, offering a novel strategy for advancing state‐of‐the‐art plastic TE materials through microstructural engineering.