Transport and mechanical properties of the double-filled p-type skutterudites La0.68Ce0.22Fe4−xCoxSb12. (15th September 2016)

• Record Type: Journal Article
• Authors: Dahal, Tulashi; Kim, Hee Seok; Gahlawat, Sonika; Dahal, Keshab; Jie, Qing; Liu, Weishu; Lan, Yucheng; White, Kenneth; Ren, Zhifeng
• Is Part Of: Acta materialia. Volume 117(2016)
• Page Start: 13
• Page End: 22
• Publication Date: 2016-09-15
• Subjects: Thermoelectricity -- Nano-structuring -- Conversion efficiency -- Mechanical strength -- Dimensionless figure of merit; Materials -- Periodicals; Materials science -- Periodicals; Materials -- Mechanical properties -- Periodicals; Metallurgy -- Periodicals; Chemistry, Inorganic -- Periodicals; 620.112
• DOI: 10.1016/j.actamat.2016.06.060
• Languages: English
• ISSNs: 1359-6454

Abstract

Abstract: Till date, the dimensionless figure of merit ( ZT ) of p -type skutterudites lags its n -type counterpart. In this work, we report improved thermoelectric performance of La/Ce double filled p -type skutterudites. The samples were synthesized by hot pressing nano-powder made by ball milling annealed ingots of La0.68 Ce0.22 Fe4−x Cox Sb12 with varying Co concentration. By tuning the Fe/Co ratio, we achieved a higher power factor (∼35 μW cm −1 K −2 at 475 °C), leading to a peak ZT of 1.15 at ∼475 °C in La0.68 Ce0.22 Fe3.5 Co0.5 Sb12 . Nanoindentation experiment carried on fine surface of the best sample reveals hardness of 5.4 GPa and modulus of elasticity of 126 GPa, which is much higher than those of Bi2 Te3 and PbTe based materials, indicating skutterudites are mechanically strong, good for some practical applications. Graphical abstract: