Synergistically Enhancing Thermoelectric Performance of n‐Type PbTe with Indium Doping and Sulfur Alloying. Issue 11 (17th December 2019)

• Record Type: Journal Article
• Authors: Wang, Dongyang; Qin, Yongxin; Wang, Sining; Qiu, Yuting; Ren, Dudi; Xiao, Yu; Zhao, Li‐Dong
• Other Names: Zhu Tiejun guestEditor.; Zhao Li‐Dong guestEditor.; Fu Chenguang guestEditor.
• Is Part Of: Annalen der Physik. Volume 532:Issue 11(2020)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2019-12-17
• Subjects: n‐type PbTe -- power factor -- thermal conductivity -- thermoelectric performance -- ZT; Physics -- Periodicals; Chemistry -- Periodicals; 530.05
• DOI: 10.1002/andp.201900421
• Languages: English
• ISSNs: 0003-3804

Abstract

Abstract: To achieve high‐performance n‐type PbTe‐based thermoelectric materials, this work provides a synergetic strategy to improve electrical transport property with indium (In) element doping and reduces thermal conductivity with sulfur (S) element alloying. In n‐type PbTe, In doping can tune the carrier density in the whole working temperature range, causing the carrier density to increase from 2.18 × 10 19 cm −3 at 300 K to 4.84 × 10 19 cm −3 at 823 K in Pb0.98 In0.005 Sb0.015 Te. The optimized carrier density can further modulate electrical conductivity and Seebeck coefficient, finally contributing to a substantial increase of power factor, and a maximum power factor increase from 19.7 µW cm −1 K −2 in Pb0.985 Sb0.015 Te to 28.2 µW cm −1 K −2 in Pb0.9775 In0.0075 Sb0.015 Te. Based on the optimally In‐doped PbTe, S alloying is introduced to suppress phonon propagation by forming a complete solid solution, which could effectively reduce lattice thermal conductivity and simultaneously benefit carrier mobility to maintain high power factor. With S alloying, the minimum lattice thermal conductivity decreases from 0.76 Wm −1 K −1 in Pb0.985 Sb0.015 Te to 0.42 Wm −1 K −1 in Pb0.98 In0.005 Sb0.015 Te0.88 S0.12 . Combining the advantages of both In doping and S alloying, the peak ZT value and averaged ZT ( ZT ave ) (300–873 K) are boosted from 1.0 and 0.60 in Pb0.985 Sb0.015 Te to 1.4 and 0.87 in Pb0.98 In0.005 Sb0.015 Te0.94 S0.06 . Abstract : The performance of n‐type PbTe can be synergistically optimized by improving power factor with indium doping and reduce the lattice thermal conductivity with point defect scattering. Finally, the maximum ZT value and average ZT ( ZT ave ) (300–873 K) are boosted from 1.0 and 0.60 in Pb0.985 Sb0.015 Te to 1.4 and 0.87 in Pb0.98 In0.005 Sb0.015 Te0.94 S0.06 .