Optimization of criteria for an efficient screening of new thermoelectric compounds: the TiNiSi structure type as a case-study

TL;DR

This paper presents a high-throughput computational screening method for discovering new thermoelectric materials, focusing on the TiNiSi structure type, and identifies promising compounds for experimental validation.

Contribution

It introduces an optimized screening approach combining DFT calculations and empirical criteria to identify potential thermoelectric compounds within the TiNiSi structure type.

Findings

12 promising semiconductors identified from 570 candidates

TiNiSi, TaNiP, and HfCoP highlighted as promising thermoelectric materials

Method effectively narrows down candidates for experimental testing

Abstract

High-throughput calculations are a very promising tool for screening a large number of compounds in order to discover new useful materials. Ternary intermetallic are thus investigated in the present work to find new compounds potentially interesting for thermoelectric applications. The screening of the stable non-metallic compounds required for such applications is obtained by calculating their electronic structure by DFT methods. In a first part, the study of the density of states at the Fermi level of well-known chemical elements and binary compounds allows to empirically optimize the selection criteria between metals and non-metals. In a second part, the TiNiSi structure-type is used as a case-study through the investigation of 570 possible compositions. This screening method leads to the selection of 12 possible semiconductors. For these selected compounds, their Seebeck coefficient and their lattice thermal conductivity are calculated in order to identify the most interesting one. TiNiSi, TaNiP or HfCoP could thus be compounds worth an experimental investigation.