Thermoelectric properties of AgGaTe$_2$ and related chalcopyrite structure materials

TL;DR

This paper analyzes the thermoelectric potential of AgGaTe$_2$ and related chalcopyrite materials, highlighting their band structure features and optimal doping conditions for high-temperature performance.

Contribution

It identifies key band structure features in chalcopyrite semiconductors that contribute to thermoelectric efficiency and suggests potential for other materials with similar properties.

Findings

AgGaTe$_2$ has a $ZT$ of 0.8 with partial optimization.

Optimal hole concentrations are identified for 700 K and 900 K.

Other chalcopyrite semiconductors may perform well if lattice thermal conductivity is lower.

Abstract

We present an analysis of the potential thermoelectric performance of p-type AgGaTe$_{2}$, which has already shown a $ZT$ of 0.8 with partial optimization, and observe that the same band structure features, such as a mixture of light and heavy bands and isotropic transport, that lead to this good performance are present in certain other ternary chalcopyrite structure semiconductors. We find that optimal performance of AgGaTe$_2$ will be found for hole concentrations between 4 $\times 10^{19}$ and 2 $\times 10^{20}$cm$^{-3}$ at 900 K, and 2 $\times 10^{19}$ and 10$^{20}$ cm$^{-3}$ at 700 K, and that certain other chalcopyrite semiconductors might show good thermoelectric performance at similar doping ranges and temperatures if not for higher lattice thermal conductivity.