Enhanced thermoelectric properties of BaZn2Sb2via a synergistic optimization strategy using co-doped Na and Sr. Issue 31 (15th July 2016)

• Record Type: Journal Article
• Authors: Yan, Ruijuan; Lv, Wanyu; Wang, Ke; Guo, Kai; Yang, Xinxin; Luo, Jun; Zhao, Jing-tai
• Is Part Of: Journal of materials chemistry. Volume 4:Issue 31(2016)
• Page Start: 12119
• Page End: 12125
• Publication Date: 2016-07-15
• Subjects: Materials -- Research -- Periodicals; Chemistry, Analytic -- Periodicals; Environmental sciences -- Research -- Periodicals; 543.0284
• DOI: 10.1039/c6ta03012b
• Languages: English
• ISSNs: 2050-7488

Abstract

Abstract : Polycrystalline samples of Ba1− x − y Na x Sr y Zn2 Sb2 (0 ≤ x ≤ 0.1, 0 ≤ y ≤ 0.1) were prepared by a solid-state reaction method and hot press sintering with the aim of achieving synergistic optimization of the power factor and thermal conductivity. Abstract : Due to rich structural features and promising thermoelectric performances, antimony-based Zintl compounds, such as AZn2 Sb2 (A = alkaline earth elements or divalent rare earth elements), have attracted much attention for both fundamental analysis and thermoelectric applications. Polycrystalline samples of Ba1− x − y Na x Sr y Zn2 Sb2 (0 ≤ x ≤ 0.1, 0 ≤ y ≤ 0.1) were prepared by a solid-state reaction method and hot press sintering with the aim of achieving synergistic optimization of the power factor and thermal conductivity. Substitution of Ba by Na could achieve optimization of the carrier concentration, leading to an increase in the power factor to 10.46 μW cm −1 K −2 at 704 K for Ba0.94 Na0.06 Zn2 Sb2 in comparison to pristine BaZn2 Sb2 (5.39 μW cm −1 K −2 at 464 K). The introduction of Sr depressed the thermal conductivity by lattice disorder. Combining the two aforementioned effects, a higher ZT value of 0.58 at 704 K was obtained for Ba0.92 Na0.06 Sr0.02 Zn2 Sb2, which is greater than that for BaZn2 Sb2 by 87% at the same temperature.