Enhanced thermoelectric performance of carbon nanotubes at elevated temperature

TL;DR

This study investigates the thermoelectric properties of (10, 0) single-walled carbon nanotubes, showing significant temperature-dependent ZT values and potential enhancements through isotope substitution and hydrogen chemisorption.

Contribution

The paper provides first-principles calculations of thermoelectric performance of (10, 0) carbon nanotubes and demonstrates methods to significantly enhance ZT at elevated temperatures.

Findings

ZT reaches 0.77 at 1000 K for p-type carriers

Isotope substitution and hydrogen chemisorption can increase ZT to 1.7

Room temperature ZT is estimated at 0.15 for p-type tubes

Abstract

The electronic and transport properties of (10, 0) single-walled carbon nanotube are studied by performing the first-principles calculations and semi-classical Boltzmann theory. It is found that the (10, 0) tube exhibits considerably large Seebeck coefficient and electrical conductivity which is highly desirable for good thermoelectric materials. Together with the lattice thermal conductivity predicted by non-equilibrium molecular dynamics simulations, the room temperature ZT value of (10, 0) tube is estimated to be 0.15 for p-type carriers. Moreover, the ZT value exhibits strong temperature dependence and can be reached to 0.77 at 1000 K. Such ZT value can be further enhanced to as high as 1.7 by isotope substitution and chemisorptions of hydrogen on the tube.