CRYSTALLOGRAPHY CONGRESS 2020

Thermo electrics Crystallography

The escalating demand for alternative, clean energy sources requires the development of new and effective materials for energy recovery, conversion, storage, and transfer. Thermoelectric (TE) materials convert heat into electrical energy and vice versa and, as such, are promising materials for waste heat reduction or recovery. Further advances in thermoelectric materials could enable stand-alone solid state heat engines. Today, applications of TE materials range from portable refrigerating bags and outdoor cell phone chargers to modern units designed for power generation in space utilizing heat from nuclear sources to power solar system exploration missions. Thermodynamic data are the solubility curves, the presence of metastable phases, polymorphs, liquid-liquid separation… They depend on multiple parameters such as temperature, pH, solvent, impurities, etc. In addition, kinetic trajectories in the phase diagram are relevant to control most of the final properties of the synthesized crystals. The path followed in the diagram controls the nucleation and growth of the crystals, and thus their number, size, and morphology.