Design of Thermoelectric Materials and Modules for Power Generation Below 300 °C and Cooling Applications Near Room Temperature

semiconducting alloys in the 1950s catalyzed advancements in the development of compact Peltier cooling devices for solid-state active temperature control. Recently, thermoelectric power generators based on the Seebeck effect have been explored as a means to recover ubiquitous waste heat for enhanced energy efficiency. However, it has become increasingly clear that the competitiveness and market viability of these devices are largely limited to near-room-temperature operation. In this perspective, a timely, application-oriented framework is provided for evaluating and selecting materials with favorable near-room-temperature Seebeck, Peltier, and Thomson effects. By integrating materials-level innovations, performance optimization strategies, and device-level considerations, promising candidates are highlighted, critical scientific challenges are identified, and actionable directions are proposed to accelerate the translation of thermoelectric materials into next-generation commercial devices with improved performance.