Advances of thermoelectric power generation for room temperature: Applications, devices, materials and beyond

With the development of economy and changes in the diversity of human life, the fields of information technology, energy saving, emission reduction, Internet of things (IoTs), as well as wearable equipment upon generating energy portably have attracted wide attention in recent years. Integrated circuit (IC) products with high-performance, low energy consumption, and user-friendly performance are required, in which the power can be self-sufficiently generated. Among these applications, thermoelectric technology based on Seebeck effect has been effectively utilized for power generation, e.g., micro thermoelectric generators (mu TEGs) with high integration and excellent compatibility virtues can be applied for medical and wearable equipment. Nevertheless, challenges like undesirable heat dissipation, small output power, low energy conversion efficiency, as well as incompatibility between thermoelectric modules and related electric loads, would limit further improvements. By optimizing thermoelectric materials and/or modifying terminal devices, amount of researches have been done to solving these problems. Here in this review, recent advances in low temperature used thermoelectric devices, consisting of constituents' selection, fabrication details, and potential applications have been systematically discussed. In addition, comprehensive strategies different from any previous works, like thermal management structure design, interdisciplinary application scenarios, energy conversion efficiency enhancements through optimizing contact and ZT, as well as adaptive module structures for irregular flat or curved surface have also been proposed, for shedding more light on the approaching potential of thermoelectric technology.