Diameter-dependent thermoelectric figure of merit in single-crystalline Bi nanowiresElectronic supplementary information (ESI) available. See DOI: 10.1039/c4nr06412g

• Main Authors: Kim, Jeongmin, Lee, Seunghyun, Brovman, Yuri M, Kim, Philip, Lee, Wooyoung
• Format: Journal Article
• Language: English
• Published: 04.03.2015
• ISSN: 2040-3364; 2040-3372
• DOI: 10.1039/c4nr06412g

The diameter-dependent thermoelectric properties of individual single-crystalline Bi nanowires grown by the on-film formation of nanowires method have been investigated. The electrical resistivity, Seebeck coefficient, and thermal conductivity were measured as functions of the nanowire diameter using an individual nanowire device. The thermoelectric figure of merit ( ZT ) calculated from the measured thermoelectric properties shows an increase from the bulk value to a maximum value of 0.28 at 109 nm-diameter, followed by a decrease upon further decreasing the diameter. This non-monotonic diameter dependence of ZT in Bi nanowires reveals simultaneous positive and negative contributions to the thermoelectric efficiency, driven by the change in intrinsic properties, which originates from the diameter-dependent classical and quantum size effects. Thermoelectric figure of merit ( ZT ) in single-crystalline Bi nanowires was obtained as a function of diameter. The non-monotonic behavior of ZT indicates that the change in the intrinsic properties originating from QSEs affects the thermoelectric properties both positively and negatively.