Host: The Japan Society of Vacuum and Surface Science
One-dimensional semiconductors are expected to have high thermoelectric performance. Single-walled carbon nanotubes (SWCNTs) are promising candidates because of their high thermoelectric performance as well as their flexibility and light weight. SWCNTs with both n-type and p-type semiconducting properties are required for SWCNT-based thermoelectric devices. Here, we focused on nitrogen-doped (N-doped) SWCNTs as a typical n-type semiconducting SWCNT. In this work, we theoretically investigated the thermoelectric properties of N-doped SWCNTs with various diameters using the Kubo-Luttinger theory, and predicted the optimum N concentration that maximizes the power factor (PF) at several temperatures. It was also shown that the maximum PF increases exponentially with decreasing diameter of SWCNTs, i.e., with increasing band gap.
