Thermoelectric Transport in Surface- and Antimony-Doped Bismuth Telluride Nanoplates
University of Texas at Austin Austin United States
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We report the in-plane thermoelectric properties of suspended Bi1xSbx 2Te3nanoplates with x ranging from 0.07 to 0.95 and thicknesses ranging from 9 to42 nm. The results presented here reveal a trend of increasing p-type behavior with increasing antimony concentration, and a maximum Seebeck coefficient and thermoelectric figure of merit at x 0.5. We additionally tuned extrinsic doping of the surface using a tetrafluoro-tetracyanoquinodimethane F4-TCNQ coating. The lattice thermal conductivity is found to be below that for undoped ultrathin Bi2Te3 nanoplates of comparable thickness and in the range of 0.20.7 W m1 K1at room temperature.