Nanoscale defect structures advancing high performance n-type PbSe thermoelectrics

[Display omitted] •Recent advances on high performance n-type PbSe thermoelectrics are discussed.•Designing defect structures to enhance thermoelectric performance are discussed.•The effects of nanoscale defect structures on charge and thermal transport properties are introduced. This short review discusses recent advances in n-type PbSe-based bulk thermoelectric materials. Their performance has rapidly progressed recently and emerges as one of most efficient n-type thermoelectrics in the mid-temperature range (500–800 K), rivaling PbTe-based materials. This success is mainly attributed to the development of new performance-enhancing strategies employing nanoscale defect structures. We introduce intrinsic thermoelectric properties of PbSe based on crystal and electronic band structures. We then discuss how nanoscale defect structures can modulate charge and phonon transport properties and serve as a key to achieving higher ZT in n-type PbSe with the examples of current state-of-the-art systems.