Predicting the optimized thermoelectric performance of MgAgSb

TL;DR

This paper uses first-principles calculations and Boltzmann theory to accurately predict and optimize the thermoelectric performance of alpha-MgAgSb, achieving a maximum ZT of 1.7 at 550 K.

Contribution

It demonstrates the importance of choosing the correct exchange-correlation functional and fine-tuning carrier concentration for optimizing thermoelectric performance.

Findings

Maximum ZT of 1.7 at 550 K

Correct semiconducting nature depends on exchange-correlation functional

Thermoelectric performance is highly temperature-dependent

Abstract

Using first-principles method and Boltzmann theory, we provide an accurate prediction of the electronic band structure and thermoelectric transport properties of alpha-MgAgSb. Our calculations demonstrate that only when an appropriate exchange-correlation functional is chosen can we correctly reproduce the semiconducting nature of this compound. By fine tuning the carrier concentration, the thermoelectric performance of alpha-MgAgSb can be significantly optimized, which exhibits a strong temperature dependence and gives a maximum ZT value of 1.7 at 550 K.