The carrier concentration in n‐type layered Bi2Te3‐based thermoelectric (TE) material is significantly impacted by the donor‐like effect, which would be further intensified by the nonbasal slip during grain refinement of crushing, milling, and deformation, inducing a big challenge to improve its TE performance and mechanical property simultaneously. In this work, high‐energy refinement and hot‐pressing are used to stabilize the carrier concentration due to the facilitated recovery of cation and anion vacancies. Based on this, combined with SbI3 doping and hot deformation, the optimized carrier concentration and high texture degree are simultaneously realized. As a result, a peak figure of merit (zT) of 1.14 at 323 K for Bi2Te2.7Se0.3 + 0.05 wt.% SbI3 sample with the high bending strength of 100 Mpa is obtained. Furthermore, a 31‐couple thermoelectric cooling device consisted of n‐type Bi2Te2.7Se0.3 + 0.05 wt.% SbI3 and commercial p‐type Bi0.5Sb1.5Te3 legs is fabricated, which generates the large maximum temperature difference (ΔTmax) of 85 K at a hot‐side temperature of 343 K. Thus, the discovery of recovery effect in high energy refinement and hot‐pressing has significant implications for improving TE performance and mechanical strength of n‐type Bi2Te3, thereby promoting its applications in harsh conditions.

The exploration of new synthesis methods is important for the improvement of the thermoelectric property of a material for the different mechanisms of microstructure fabrication, surface activity modulation, and particle refinement. Herein, we prepared p-Bi2Te3 bulk materials by a simple synthesis method of the plasma-assisted ball milling, which yielded finer nanopowders, higher texture of in-plane direction, and higher efficiency compared to the traditional ball milling, favoring the simultaneous improvement of electrical and thermal properties. When combined with the Te liquid sintering, nano-/microscale hierarchical pores were fabricated and the carrier mobility was also increased, which together resulted in the low lattice thermal conductivity of 0.52 W·m–1·K–1 and the high power factor of 43.4 μW·cm–1·K–2 at 300 K, as well as the ranking ahead zT of 1.4@375 K. Thus, this work demonstrated the advantages of plasma-assisted ball milling in highly efficient synthesis of p-type Bi2Te3 with promising thermoelectric performance, which can also be utilized to prepare other thermoelectric materials.

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