A first-principles theoretical study on the potential thermoelectric properties of MgH2 and CaH2. (8th February 2019)

• Record Type: Journal Article
• Authors: Wang, Yunxia; Ohishi, Yuji; Kurosaki, Ken; Muta, Hiroaki
• Is Part Of: Materials research express. Volume 6:Number 5(2019)
• Publication Date: 2019-02-08
• Subjects: thermoelectric materials -- first-principles calculation -- hydrides -- electrical conductivity -- thermal conductivity; Materials science -- Research -- Periodicals; Materials science -- Periodicals; 620.11
• DOI: 10.1088/2053-1591/ab0346
• Languages: English
• ISSNs: 2053-1591

Abstract

Abstract: First-principles calculations, Boltzmann transport equations, and a modified Slack's model were used to investigate the Seebeck coefficient S, electrical conductivity σ, and thermal conductivity κ of hydrides MgH2 and CaH2 . As a result, a largest zT value around 0.38 and 0.55 at 1000 K could be achieved when carrier concentratio n n ∼ 1.7 × 10 21 cm −3 a n d n ∼ 7.4 × 10 20 cm −3 in the p -type MgH2 and CaH2, respectively. Higher zT values (>1) could be achieved by reduction of the high thermal conductivity. The results of our study gave a support that hydrides MgH2 and CaH2 could be promising as thermoelectric materials.