Solution Synthesis Empowers Control in Inorganic Thermoelectric Materials

Thermoelectricity is the process of directly converting heat into electricity and vice versa, offering an environmentally sustainable means to generate electricity from wasted heat. To enhance the efficiency of this conversion, it's essential to precisely control various structural aspects beyond just the crystal structure. These aspects include defects, grain size, orientation, and interfaces. Conventional solid-state methods have limitations in achieving such precise control.<br/><br/>In recent years, solution-based techniques have garnered significant interest as a cost-effective and easily scalable approach for manufacturing high-performance thermoelectric materials. In this method, a powdered material is first prepared in a solution and then subjected to purification and thermal processing to produce the desired dense polycrystalline material. Unlike traditional methods, solution-based syntheses offer an exceptional level of control over various particle properties, including size, shape, crystal structure, composition, and surface chemistry. This precise control over the properties of the powder creates distinct opportunities for crafting thermoelectric materials with precisely tailored microstructural characteristics.<br/><br/>Throughout our research, we will illustrate various instances where exercising control over distinct nanoparticle characteristics, such as surface attributes or stoichiometry, directly influences specific properties of the dense material, thereby enabling us to fine-tune its performance optimally. Our focus will be particularly directed towards Ag₂Se, a thermoelectric material of great significance, especially in applications near room temperature.