Thermoelectricity in semiconductor nanowires

In this paper, we provide a comprehensive review on recent advances in the development of semiconductor nanowires for thermoelectric energy conversion. Semiconductor nanowires can exhibit novel properties in the electron and phonon transport as their diameters approach the characteristic length scales of the material such as the electron wavelength and the phonon mean free path. These size effects in semiconducting nanowires are discussed as a means to enhance the thermoelectric properties of the nanowires over their bulk counterparts. Challenges for the enhancement are also identified. We present recent theoretical and experimental results on various thermoelectric nanowires including Si, Ge, InAs, Bi, Bi-Te and Bi-Sb nanowires. Various characterization techniques for the accurate electrical and thermal measurements of individual nanowires are also covered. Finally, we mention briefly the recent efforts to fabricate thermoelectric devices using nanowire arrays.