High-Temperature Thermoelectric Properties of Sol-Gel Processed Ca2.5Ag0.3RE0.2Co4O9 (RE: Y and Rare-Earths) Materials

Küçük Resim Yok

Tarih

2020

Dergi Başlığı

Dergi ISSN

Cilt Başlığı

Yayıncı

Wiley-V C H Verlag Gmbh

Erişim Hakkı

info:eu-repo/semantics/closedAccess

Özet

Herein, dually doped Ca2.5Ag0.3RE0.2Co4O9 (RE: La, Pr, Nd, Sm, Gd, Dy, Er, Yb, Eu, Tb, Ho, Lu, Ce, and Y) samples are synthesized by sol-gel technique and consolidated by cold pressing under high pressure to systematically scrutinize the influences of Y and rare-earth dually doping with Ag on transport properties of Ca3Co4O9 for high-temperature thermoelectric (TE) applications. Characterization results reveal that targeted phase is successfully produced, and doping of the compositions is provided. Doping of Y and rare-earth elements together with Ag into the Ca2+ site is effective in increasing the Seebeck coefficient and decreasing the electrical resistivity of the samples, thanks to the reduction in carrier concentration. Thermal conductivity of the samples is reduced related to the lower relative densities and alloy scattering originated from dually doping. Among the samples, Ca2.5Ag0.3Ho0.2Co4O9 and Ca2.5Ag0.3Eu0.2Co4O9 exhibit the highest power factor (PF) values of 0.65 and 0.62 mW m(-1) K-2 at 800 degrees C, respectively. These results are quite high for bulk oxide TE materials which can be assessed as potential oxide TE materials for high-temperature TE power generation.

Açıklama

Anahtar Kelimeler

dually doping, figures of merit, oxide thermoelectrics, sol-gel, thermoelectric properties

Kaynak

Physica Status Solidi A-Applications and Materials Science

WoS Q Değeri

Q3

Scopus Q Değeri

Q2

Cilt

217

Sayı

15

Künye