Issue 37, 2022

Synergistically enhanced electrical transport properties of SrTiO3via Fermi level regulation and modulation doping

Abstract

SrTiO3 has gained wide attention as an oxide thermoelectric material due to its high Seebeck coefficient and excellent high-temperature thermal stability. However, its intrinsic insulatory properties hinder its development as a thermoelectric material. Herein, we synergistically improved the electrical transport properties of SrTiO3 by increasing carrier concentration and maintaining high carrier mobility via Fermi level regulation and modulation doping through co-doping and compositing. Nb and La co-doping notably heightened the carrier concentration and regulated the Fermi level in the conduction band, resulting in an enhanced ZT value from that of an insulator in SrTiO3 to 0.033 in Sr0.875La0.125Ti0.85Nb0.15O3 at 923 K. The subsequent TiB2 compositing simultaneously improved carrier concentration (4.82 × 1017 cm3) and afforded high carrier mobility (3.55 × 104 cm2 V−1 S−1) in the Sr0.875La0.125Ti0.85Nb0.15O3 + 4% TiB2 sample at 923 K. The combination of synergistically improved carrier concentration and retained high carrier mobility resulted in an enhanced power factor (11.04 μW cm−1 K−2 at 923 K), maximum ZT (0.23 at 923 K) and average ZT (0.15 at 473–923 K) in Sr0.875La0.125Ti0.85Nb0.15O3 + 4% TiB2 through co-doping and compositing, which matches those of many excellent SrTiO3-based materials. Our study demonstrated that the thermoelectric properties of SrTiO3 could be improved via synergistically enhanced electrical transport properties through Fermi level regulation and modulation doping via co-doping and compositing, which will inspire further research on SrTiO3 and other oxide thermoelectric materials with mediocre electrical transport properties.

Graphical abstract: Synergistically enhanced electrical transport properties of SrTiO3via Fermi level regulation and modulation doping

Supplementary files

Article information

Article type
Paper
Submitted
21 feb 2022
Accepted
13 mar 2022
First published
17 mar 2022

J. Mater. Chem. C, 2022,10, 13851-13859

Synergistically enhanced electrical transport properties of SrTiO3via Fermi level regulation and modulation doping

D. Li, D. Wang, X. Zhang and L. Zhao, J. Mater. Chem. C, 2022, 10, 13851 DOI: 10.1039/D2TC00719C

To request permission to reproduce material from this article, please go to the Copyright Clearance Center request page.

If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given.

If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page.

Read more about how to correctly acknowledge RSC content.

Social activity

Spotlight

Advertisements