Important role of Cu in suppressing bipolar conduction in Bi-rich (Bi,Sb)2Te3

Kyu Hyoung Lee, Weon Ho Shin, Hyun Sik Kim, Hyun joon Cho, Sung Wng Kim, Sang il Kim

Research output: Contribution to journalArticlepeer-review

7 Scopus citations


Cu doping has been known to enhance thermoelectric performance of p-type (Bi,Sb)2Te3 alloys by suppressing bipolar conduction at higher temperatures. However, detailed mechanisms are not provided yet. Herein, we investigate the unchallenged role of Cu doping in (Bi,Sb)2Te3 alloys by means of Bi-rich compositions of Bi0.6Sb1.4Te3 and Bi0.7Sb1.3Te3, which were chosen since they exhibit much inferior thermoelectric performance owing to severe bipolar conduction. It was found that Cu doping increases non-degenerate mobility and density-of-states effective mass of valence band as well as hole concentration. Small amount of Cu doping enhanced maximum thermoelectric figure-of-merit of Bi0.6Sb1.4Te3 composition from 0.25 to 0.98.

Original languageEnglish
Pages (from-to)225-229
Number of pages5
JournalScripta Materialia
StatePublished - Sep 2020


  • Bipolar conduction
  • Doping
  • Effective mass
  • Thermoelectric
  • Weighted mobility


Dive into the research topics of 'Important role of Cu in suppressing bipolar conduction in Bi-rich (Bi,Sb)2Te3'. Together they form a unique fingerprint.

Cite this