Optimizing the Thermo-physical Properties of Fluorinated Carbon Nanotube for Thermoelectric Applications

Abstract

ABSTRACT In a nondegenerate fluorinated single-walled carbon nanotube (FSWCNT) in the hypersound domain, q` 1, where q is the acoustic wavenumber and ` is the carrier mean free path, a theoretical study of semiclassical carrier miniband transport across a periodic potential was carried out. First, the effect of an acoustic wave on FSWCNT was investigated, and it was discovered that high-frequency carrier dynamics can be created, though the wavenumber or wave amplitude is critical. Depending on the wave amplitude and the carrier’s initial position in the acoustic wave, there were two dynamical regimes. Bloch-like oscillations could be induced by applying a large enough potential amplitude/wavenumber, resulting in ultra-high negative differential velocity, or the carrier could be dragged through the FSWCNT and permitted to drift in periodic orbits with frequencies far above the gigahertz frequencies (GHz) of the acoustic wave. A high negative differential velocity induces charge domains in FSWCNT at transitions between these two carrier dynamic regimes, which generated extra features in the current oscillations. Secondly, invoking an analytical technique which is traceable and the phonon LBM, the dimensionless figure of merit (ZT ) for FSWCNT was explored. The ZT was found to be substantially influenced by the FSWCNT parameters ∆s, ∆z, Eo and no. At room temperatures and beyond, optimizing ∆s, ∆z and no resulted in a ZT greater than 6 (i.e., ZT > 6). As a result of the high ZT achieved, the FSWCNT can be considered a good thermoelement material.