3D Conformal Printing and Photonic Sintering of High‐Performance Flexible Thermoelectric Films Using 2D Nanoplates

Flexible thermoelectric (TE) devices hold great promise for energy harvesting and cooling applications, with increasing signi cance to serve as perpetual power sources for exible electronics and wearable devices. Despite unique and superior TE properties widely reported in nanocrystals, transforming these nanocrystals into exible and functional forms remains a major challenge. Herein, demonstrated is a transformative 3D conformal aerosol jet printing and rapid photonic sintering process to print and sinter solution-processed Bi2Te2.7Se0.3 nanoplate inks onto virtually any exible substrates. Within seconds of photonic sintering, the electrical conductivity of the printed lm is dramatically improved from nonconductive to 2.7 × 104 S m−1. The lms dem- onstrate a room temperature power factor of 730 μW m−1 K−2, which is among the highest values reported in exible TE lms. Additionally, the lm shows negligible performance changes after 500 bending cycles. The highly scalable and low-cost fabrication process paves the way for large-scale manufacturing of exible devices using a variety of high-performing nanoparticle inks.