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Self‐Tuning the Carrier Concentration of PbTe/Ag 2 Te Composites with Excess Ag for High Thermoelectric Performance
Author(s) -
Pei Yanzhong,
May Andrew F.,
Snyder G. Jeffrey
Publication year - 2011
Publication title -
advanced energy materials
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 10.08
H-Index - 220
eISSN - 1614-6840
pISSN - 1614-6832
DOI - 10.1002/aenm.201000072
Subject(s) - materials science , thermoelectric effect , dopant , doping , composite material , temperature gradient , thermoelectric materials , solubility , chemical engineering , optoelectronics , thermodynamics , thermal conductivity , chemistry , physics , quantum mechanics , engineering
Thermoelectric materials can be optimized by tuning the carrier concentration with chemical doping. However, because the optimum dopant concentration typically increases with temperature, the optimum efficiency can not normally be achieved for a uniform material in a temperature gradient. Here, we show Ag‐doped PbTe/Ag 2 Te composites exhibit high thermoelectric performance (∼50% greater than La‐doped composites) because of a temperature induced gradient in the doping concentration caused by the temperature‐dependent solubility of Ag in the PbTe matrix. This demonstrates a new mechanism to achieve a higher thermoelectric efficiency afforded by a given material system, and should be applicable to other thermoelectric materials.