Enhancement of thermoelectric properties of Co4Sb12 Skutterudite by Al and La double filling

This work reports the enhancement of thermoelectric properties of La0.5Co4Sb12 compound due to addition of Al. A polycrystalline AlxLa0.5Co4Sb12 (0 ≤ x ≤ 0.5) skutterudites were successfully prepared by mechanical alloying and spark plasma sintering techniques. The characterization of phase stru...

Full description

Saved in:

Bibliographic Details
Published in:	Journal of solid state chemistry Vol. 284; p. 121205
Main Authors:	Bashir, Mohamed Bashir Ali, Mohd Sabri, Mohd Faizul, Said, Suhana Mohd, Miyazaki, Yuzuru, Badruddin, Irfan Anjum, Ameer Shnawah, Dhafer Abdul, Salih, Ethar Yahya, Abushousha, Sabir, Elsheikh, Mohamed Hamid
Format:	Journal Article
Language:	English
Published:	Elsevier Inc 01-04-2020
Subjects:	Double filling Mechanical alloying Skutterudite material Thermoelectric Skutterudite material Thermoelectric Double filling Mechanical alloying
Online Access:	Get full text
Tags:	Add Tag No Tags, Be the first to tag this record!

Description
Summary:	This work reports the enhancement of thermoelectric properties of La0.5Co4Sb12 compound due to addition of Al. A polycrystalline AlxLa0.5Co4Sb12 (0 ≤ x ≤ 0.5) skutterudites were successfully prepared by mechanical alloying and spark plasma sintering techniques. The characterization of phase structure and morphology of AlxLa0.5Co4Sb12 bulk samples are examined by XRD and SEM-EDX analysis. The results revealed that the main phase of CoSb3 skutterudite structure with a small amount of Al were distributed in the grain boundaries for the most of AlxLa0.5Co4Sb12 samples. The thermoelectric measurements of consolidated samples were evaluated from room temperature to 800 K. The electrical resistivity remarkably reduced through the addition of Al to the lowest value of 7.6 μΩm at room temperature for Al0.05La0.5Co4Sb12 sample. Moreover, the absolute Seebeck coefficient was significantly improved by Al addition and the highest value of 193 μV/K was observed at 789 K for Al0.05La0.5Co4Sb12 sample. Furthermore, the same formulation showed a significant enhancement on the power factor that reached the maximum value of 4.02 × 10−3 W/mK2 at 789 K. The thermal conductivity and lattice thermal conductivity were significantly minimized to the value of 1.1 W/mK (at 789 K) and 0.64 W/mK (at 595 K), respectively for Al0.3La0.5Co4Sb12 due to the enhancement of phonon scattering. Additionally, a comprehensive improvement on the dimensionless figure of merit value ZT of 1.36 for Al0.05La0.5Co4Sb12 at 789 K has been achieved. [Display omitted] •AlxLa0.5Co4Sb12 skutterudite samples were prepared using mechanical alloying and spark plasma sintering.•Al addition serve to decrease the electrical resistivity of La0.5Co4Sb12 skutterudites.•A low thermal conductivity of Al0.05La0.5Co4Sb12 was achieved.•Concurrent improvement of electrical conductivity and Seebeck coefficient was achieved.•Significantly increased power factor of 4.02 × 10−3 W/mk2 at 789 K.
ISSN:	0022-4596 1095-726X
DOI:	10.1016/j.jssc.2020.121205