Modulation Doping Enables Ultrahigh Power Factor and Thermoelectric ZT in n-Type Bi₂ Te_2.7 Se_0.3.

ABSTRACT: Bismuth telluride-based thermoelectric (TE) materials are historically recognized as the best p-type (ZT = 1.8) TE materials at room temperature. However, the poor performance of n-type (ZT≈1.0) counterparts seriously reduces the efficiency of the device. Such performance imbalance severely impedes its TE applications either in electrical generation or refrigeration. Here, a strategy to boost n-type Bi₂ Te_2.7 Se_0.3 crystals up to ZT = 1.42 near room temperature by a two-stage process is reported, that is, step 1: stabilizing Seebeck coefficient by CuI doping; step 2: boosting power factor (PF) by synergistically optimizing phonon and carrier transport via thermal-driven Cu intercalation in the van der Waals (vdW) gaps. Theoretical ab initio calculations dis

SUBMITTER: Chen CL 

PROVIDER: S-EPMC9284191 | biostudies-literature | 2022 Jul

REPOSITORIES: biostudies-literature