Enhanced thermoelectric properties in Ge-doped and single-filled skutterudites prepared by unique melt-spinning method. Issue 11 (1st August 2018)

• Record Type: Journal Article
• Authors: Shaheen, Nusrat; Javed, Muhammad Sufyan; Shah, Hidayat Ullah; Hussain, Shahid; Ahmad, Muhammad Ashfaq; Raza, Rizwan; Saleem, Muhammad; Zhou, Xiaoyuan
• Is Part Of: Ceramics international. Volume 44:Issue 11(2018)
• Page Start: 12610
• Page End: 12614
• Publication Date: 2018-08-01
• Subjects: Thermoelectric properties -- Phonon scattering -- Ge doping -- Nd filler -- Fast preparation; Ceramics -- Periodicals; Céramique industrielle -- Périodiques; Ceramics; Periodicals; Electronic journals; 666
• DOI: 10.1016/j.ceramint.2018.04.058
• Languages: English
• ISSNs: 0272-8842

Abstract

Abstract: In this paper, we determined an effective substitution of Ge at Sb sites in Nd-filled p-type skutterudites, a series of Nd.9 Fe2 Co2 Sb12-x Gex compounds with compositions of x = 0, 0.1, 0.2, 0.3 and 0.4 were synthesized by home-made induction melting, assembled inside the glove box and followed by spark plasma sintering process (SPS). The thermoelectric properties are investigated as a function of Ge doping content with fixed Nd-filler at 0.9 and the formation of skutterudite phase is characterized by X-ray diffraction. All samples possess positive Seebeck coefficients, representing effective p-type doping. It is observed that the electrical conductivity decreases with decreasing Ge doping concentrations while increased with temperature due to bipolar effect. The lightly doped samples (x = 0.1 and 0.2) have lower lattice thermal conductivity over the entire temperature range, in which x = 0.2 sample shows the highest ZT value of 0.82 at 700 K, which is 30% higher than that of the Ge-free sample. The improvement in ZT can be attributed to the optimized carrier concentration and reduced thermal conductivity. The enhancement of ZT through Ge doping, coupled with drastically reduced processing time, shows that these compounds may have great potential in application as p-type segments of the thermoelectric devices.