Ultrahigh thermoelectric performance in polymeric multi-heterojunction

Organic plastics-based flexible thermoelectric devices have shown important application prospects in wearables, self-powered electronics, and two-dimensional in-plane cooling applications. However, their practical applications have long been restricted by the inferior properties of thermoelectric polymers, mainly due to the non-periodic polymetric structures. Recently, Wang et al. developed a novel polymeric multi-heterojunction (PMHJ) architecture featuring periodic dual-heterojunction, facilitating a substantial enhancement of thermoelectric performance. By carefully constructing the PMHJ films and further tuning the transport properties with proper doping, a remarkably high ZT value of 1.28 at 368 K was obtained. On this basis, full-scale and large-area flexible thermoelectric generators based on PMHJ were fabricated, showing great potential for cost-effective wearable electronics. In this highlight, we intend to emphasize the importance of this research especially for organic flexible thermoelectricity. Besides, we aim to explore the feasibility of the PMHJ concept for developing high-performance flexible thermoelectrics based on other polymers. This might provide some insights for specific future research in this direction.