High-temperature thermoelectric properties of Sm3+-doped Ca3Co4O9+δ fabricated by spark plasma sintering. Issue 6 (15th April 2018)

• Record Type: Journal Article
• Authors: Cha, J.S.; Choi, S.-M.; Kim, G.H.; Kim, S.-J.; Park, K.
• Is Part Of: Ceramics international. Volume 44:Issue 6(2018)
• Page Start: 6376
• Page End: 6383
• Publication Date: 2018-04-15
• Subjects: Sintering -- Electron microscopy -- Sol–gel processes -- Electrical conductivity -- Electrical properties -- Microstructure-final; Ceramics -- Periodicals; Céramique industrielle -- Périodiques; Ceramics; Periodicals; Electronic journals; 666
• DOI: 10.1016/j.ceramint.2018.01.030
• Languages: English
• ISSNs: 0272-8842

Abstract

Abstract: Ca3- x Sm x Co4 O9+ δ (0 ≤ x ≤ 0.3) samples were fabricated by the sol-gel method followed by spark plasma sintering in vacuum. The high-temperature thermoelectric properties of the Ca3- x Sm x Co4 O9+ δ were also studied, with an emphasis placed on the partial substitution of Sm 3+ for Ca 2+ . The sintered Ca3- x Sm x Co4 O9+ δ formed a monoclinic Ca3 Co4 O9 phase and exhibited fine lamellar grains and dense morphology. With increased Sm 3+ content, the electrical and thermal conductivities decreased, whereas the Seebeck coefficient significantly increased. Of the prepared samples, Ca2.7 Sm0.3 Co4 O9+ δ had the largest dimensionless figure-of-merit (0.175) at 800 °C. The results showed that the partial substitution of Sm 3+ for Ca 2+ in Ca3 Co4 O9+ δ is effective for enhancing its thermoelectric properties.