Recyclable, Healable, and Stretchable High-Power Thermoelectric Generator

Direct energy conversion based on thermoelectric (TE) materials is a long-term and maintenance-free energy harvesting technique, and therefore is very promising for self-powered wearable electronics. Yet, it is challenging to achieve high-performance stretchable, healable, and even recyclable thermoelectric generators (TEGs) without compromising TE conversion performance due to the intrinsic mechanical rigidity and brittleness of the inorganic TE materials. Herein, recyclable, healable, and stretchable TEGs (RHS-TEGs) are reported that are assembled from commercial Bi₂Te₃ and Sb₂Te₃ TE legs generating superior power density via the use of liquid metal as interconnects and dynamic covalent thermoset polyimine as encapsulation. The TEGs fabricated using this strategy are endowed with excellent TE performance, mechanical compliance, and healing and recycling capabilities. The normalized output power density and mechanical stretchability can reach up to 1.08 µW cm⁻²·K² and 50%, respectively. After healing and recycling, the TEGs show output performance comparable to the original devices. The TEGs also exhibit high reliability and stability under cyclic deformation. This study paves the way for sustainable application of TEGs as energy harvesters to power wearable electronics using body heat.