Additive Manufacturing of Colloidal Nanocrystals for Flexible Thermoelectric Generators

2D Chalcogenides, a narrow gap layered semiconductor and a topological insulator has been reported to have excellent room temperature thermoelectric performances. Alloying and nanostructuring of the material have been widely studied for reducing the lattice thermal conductivity (Κ L ) of the materials to enhance the thermoelectric figure of merit (ZT). But the performance of printed thermoelectric devices is significantly low compared to bulk counterparts due to low density and porosity, here we report interface engineering and Nano inclusion in the crystals as an effective way to increase the performance of thermoelectric materials. This work demonstrates the scalable solvothermal synthesis of crystalline nanomaterials with engineered defects and interface engineering to improve the thermoelectric performance of the colloidal nano-inks. The engineered nanomaterials are transformed into devices using multiple additive manufacturing methods including Screen printing, Aerosol Jet Printing, Plasma Jet Printing, and Direct Writing. The low-cost scalable additive manufacturing methods and interface engineering developed in this work demonstrate a significant advance in the field of high-performing low-cost thermoelectric generators, advancing the commercial viability of the technology for energy harvesting, sensing, and cooling applications.