TY - JOUR
T1 - Dual defect system of tellurium antisites and silver interstitials in off-stoichiometric Bi 2 (Te,Se) 3+: Y causing enhanced thermoelectric performance
AU - Kim, Cham
AU - Lopez, David Humberto
AU - Kim, Dong Hwan
AU - Kim, Hoyoung
N1 - Publisher Copyright:
© 2019 The Royal Society of Chemistry.
PY - 2019
Y1 - 2019
N2 - Enhancement in the thermoelectric performance of n-type Bi 2 (Te,Se) 3 was accomplished by forming a dual defect system composed of Te- and Ag-related defects. Te-rich Bi 2 (Te,Se) 3+y , which has antisite defects generated by an excess of Te, was prepared via a conventional melting process. We devised a one-pot process in which Ag nanoparticles were deposited onto the Te-rich Bi 2 (Te,Se) 3+y as soon as they were chemically synthesized, followed by a sintering compaction; thus, we aimed at selective insertion of Ag atoms into the interstitial sites of the Te-rich Bi 2 (Te,Se) 3+y . The resulting Ag interstitials interact with the Te antisite defects to vary the thermoelectric transport properties of the product. We endeavored to balance the concentration of the defects to maximize the phonon glass electron crystal (PGEC) characteristic of the product, resulting in excellent thermoelectric performance in low temperature regions-we achieved the highest ZT average values, below 150 °C (ZT ave = 1.18 (25-100 °C) and 1.15 (25-150 °C)), ever reported for n-type Bi 2 (Te,Se) 3 materials.
AB - Enhancement in the thermoelectric performance of n-type Bi 2 (Te,Se) 3 was accomplished by forming a dual defect system composed of Te- and Ag-related defects. Te-rich Bi 2 (Te,Se) 3+y , which has antisite defects generated by an excess of Te, was prepared via a conventional melting process. We devised a one-pot process in which Ag nanoparticles were deposited onto the Te-rich Bi 2 (Te,Se) 3+y as soon as they were chemically synthesized, followed by a sintering compaction; thus, we aimed at selective insertion of Ag atoms into the interstitial sites of the Te-rich Bi 2 (Te,Se) 3+y . The resulting Ag interstitials interact with the Te antisite defects to vary the thermoelectric transport properties of the product. We endeavored to balance the concentration of the defects to maximize the phonon glass electron crystal (PGEC) characteristic of the product, resulting in excellent thermoelectric performance in low temperature regions-we achieved the highest ZT average values, below 150 °C (ZT ave = 1.18 (25-100 °C) and 1.15 (25-150 °C)), ever reported for n-type Bi 2 (Te,Se) 3 materials.
UR - http://www.scopus.com/inward/record.url?scp=85059559256&partnerID=8YFLogxK
U2 - 10.1039/c8ta05261a
DO - 10.1039/c8ta05261a
M3 - Article
AN - SCOPUS:85059559256
SN - 2050-7488
VL - 7
SP - 791
EP - 800
JO - Journal of Materials Chemistry A
JF - Journal of Materials Chemistry A
IS - 2
ER -