Materials design criteria for ultra-high thermoelectric power factors in metals

Fuente: arXiv
Saved in:
Bibliographic Details
Main Authors: Graziosi, Patrizio, Mehnert, Kim-Isabelle, Dutt, Rajeev, Bos, Jan-Willem G., Neophytou, Neophytos
Format: Preprint
Published: 2025
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866909460721565696
author Graziosi, Patrizio
Mehnert, Kim-Isabelle
Dutt, Rajeev
Bos, Jan-Willem G.
Neophytou, Neophytos
author_facet Graziosi, Patrizio
Mehnert, Kim-Isabelle
Dutt, Rajeev
Bos, Jan-Willem G.
Neophytou, Neophytos
contents Metals have high electronic conductivities, but very low Seebeck coefficients, which traditionally make them unsuitable for thermoelectric materials. Recent studies, however, showed that metals can deliver ultra-high thermoelectric power factors (PFs) under certain conditions. In this work, we theoretically examine the electronic structure and electronic transport specifications which allow for such high PFs. Using Boltzmann transport (BTE) simulations and a multi-band electronic structure model, we show that metals with: i) high degree of transport asymmetry between their bands, ii) strong inter-band scattering, and iii) a large degree of band overlap, can provide ultra-high power factors. We show that each of these characteristics adds to the steepness of the transport distribution function of the BTE, which allows for an increase of the Seebeck coefficient to sizable values, simultaneously with an increase in the electrical conductivity. This work generalizes the concept that transport asymmetry (i.e., mixture of energy regions of high and low contributions to the electrical conductivity), through a combination of different band masses, scattering strengths, or energy filtering scenarios, etc., can indeed result in very high thermoelectric power factors, even in the absence of a material bandgap. Under certain conditions, transport asymmetry can over-compensate any performance degradation to the PF due to bipolar conduction and the naturally low Seebeck coefficients that otherwise exist in this class of materials.
format Preprint
id arxiv_https___arxiv_org_abs_2501_10790
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle Materials design criteria for ultra-high thermoelectric power factors in metals
Graziosi, Patrizio
Mehnert, Kim-Isabelle
Dutt, Rajeev
Bos, Jan-Willem G.
Neophytou, Neophytos
Materials Science
Metals have high electronic conductivities, but very low Seebeck coefficients, which traditionally make them unsuitable for thermoelectric materials. Recent studies, however, showed that metals can deliver ultra-high thermoelectric power factors (PFs) under certain conditions. In this work, we theoretically examine the electronic structure and electronic transport specifications which allow for such high PFs. Using Boltzmann transport (BTE) simulations and a multi-band electronic structure model, we show that metals with: i) high degree of transport asymmetry between their bands, ii) strong inter-band scattering, and iii) a large degree of band overlap, can provide ultra-high power factors. We show that each of these characteristics adds to the steepness of the transport distribution function of the BTE, which allows for an increase of the Seebeck coefficient to sizable values, simultaneously with an increase in the electrical conductivity. This work generalizes the concept that transport asymmetry (i.e., mixture of energy regions of high and low contributions to the electrical conductivity), through a combination of different band masses, scattering strengths, or energy filtering scenarios, etc., can indeed result in very high thermoelectric power factors, even in the absence of a material bandgap. Under certain conditions, transport asymmetry can over-compensate any performance degradation to the PF due to bipolar conduction and the naturally low Seebeck coefficients that otherwise exist in this class of materials.
title Materials design criteria for ultra-high thermoelectric power factors in metals
topic Materials Science
url https://arxiv.org/abs/2501.10790