Precursor-Led Grain Boundary Engineering for Superior Thermoelectric Performance in Niobium Strontium Titanate.
ACS Appl Mater Interfaces
; 15(10): 13097-13107, 2023 Mar 15.
Article
en En
| MEDLINE
| ID: mdl-36854123
ABSTRACT
We present a novel method to significantly enhance the thermoelectric performance of ceramics in the model system SrTi0.85Nb0.15O3 through the use of the precursor ammonium tetrathiomolybdate (0.5-2% w/w additions). After sintering the precursor-infused green body at 1700 K for 24 h in 5% H2/Ar, single-crystal-like electron transport behavior developed with electrical conductivity reaching â¼3000 S/cm at â¼300 K, almost a magnitude higher than that in the control sample. During processing, the precursor transformed into MoS2, then into MoOx, and finally into Mo particles. This limited grain growth promoted secondary phase generation but importantly helped to reduce the grain boundary barriers. Samples prepared with additions of the precursor exhibited vastly increased electrical conductivity, without significant impact on Seebeck coefficients giving rise to high power factor values of 1760 µW/mK2 at â¼300 K and a maximum thermoelectric figure-of-merit zT of 0.24 at 823 K. This processing strategy provides a simple method to achieve high charge mobility in polycrystalline titanate and related materials and with the potential to create "phonon-glass-electron-crystal" oxide thermoelectric materials.
Texto completo:
1
Bases de datos:
MEDLINE
Tipo de estudio:
Prognostic_studies
Idioma:
En
Revista:
ACS Appl Mater Interfaces
Asunto de la revista:
BIOTECNOLOGIA
/
ENGENHARIA BIOMEDICA
Año:
2023
Tipo del documento:
Article
País de afiliación:
Reino Unido