제목: Ink processing for inorganic thermoelectric materials and devices

내용: Heat is omnipresent in natural and artificial environments, more than 60% of which is dissipated. Thermoelectric (TE) power generation can provide a unique solution to convert this dissipated, wasted heat into useful energy, that is, electricity. Generally, TE conversion efficiency depends on the material properties and design of the module structure. However, despite the development of highly efficient TE materials, module engineering is rather less advanced and is still fabricated by the traditional multi-step process of materials synthesis, dicing, and assembly, restricting the available design of modules to that of planar structures. At this moment, the printing technology can maximize the flexibility in the design and fabrication of TE modules into more efficient structures. Furthermore, the printing process can significantly reduce the processing cost for the fabrication of TE modules owing to lower energy input and a simplified assembly process. Herein, I present the development of the printing process applied to a range of different TE materials of Bi2Te3, BiSbTe, PbTe, and Cu2Se-based inorganic alloys. The molecular complexes or particle-based inks were formulated with the tailored surfaces of particles, achieving the suitable printability of the TE inks to the solution-processed thin films or extrusion-based 3D printing. The geometrically designed printed TE materials were assembled into power generating systems, in which high efficiencies of energy conversion were achieved by the optimization of heat transfer. Finally, I present the extension of these chemical designs of inorganic inks into functional semiconductors for electronics.