Enhanced thermoelectric properties induced by chemical pressure in Ca3Co4O9
Küçük Resim Yok
Tarih
2014
Yazarlar
Dergi Başlığı
Dergi ISSN
Cilt Başlığı
Yayıncı
Elsevier Sci Ltd
Erişim Hakkı
info:eu-repo/semantics/closedAccess
Özet
We report the investigation of boron substitution on structural, electrical, thermal, and thermoelectric properties of Ca-3_xBxCo4O9 (x=0, 0.5, 0.75, and 1) in the temperature range between 300 K and 5 K. X-ray diffraction studies show that the Ca3Co4O9 phase is successfully preserved as the majority phase in the x=0.5 sample despite the small size of boron ions. Electrical transport measurements confirm that B3+ substitution for Ca2+ causes an increase in resistivity due to the decrease in carrier concentration. x=0.5 sample is found to have a Seebeck coefficient of 181 mu V/K at room temperature which is similar to 1.5 times higher than that of the pure Ca3Co4O9. Our results indicate that the chemical pressure due to the large ionic radii difference between B3+ (0.27 angstrom) and Ca2+ (1 angstrom) enhances the thermoelectric properties as long as the unique crystal structure of Ca3Co4O9 is preserved. (c) 2013 Elsevier Ltd and Techna Group S.r.l. All rights reserved.
Açıklama
Anahtar Kelimeler
Ca3Co4O9, Thermopower, Chemical pressure
Kaynak
Ceramics International
WoS Q Değeri
Q1
Scopus Q Değeri
Q1
Cilt
40
Sayı
4
