Effects of alkali metal element substitution on the thermoelectric properties of β-Zn4Sb3. (19th February 2020)

• Record Type: Journal Article
• Authors: Liu, Mian; Xu, Kun; Qin, Xiaoying; Liu, Changsong; Li, Zhe
• Is Part Of: Materials research express. Volume 6:Number 12(2019)
• Publication Date: 2020-02-19
• Subjects: thermoelectric material -- thermoelectric performance -- Zn4Sb3; Materials science -- Research -- Periodicals; Materials science -- Periodicals; 620.11
• DOI: 10.1088/2053-1591/ab726f
• Languages: English
• ISSNs: 2053-1591

Abstract

Abstract: The effects of alkali metal elements Na, Li, and K on the electronic structure and thermoelectric properties of β -Zn4 Sb3 were extensively studied based on first-principles electronic structure calculations and Boltzmann transport theories. We found that these alkali metal elements with s orbitals could bring resonant distortion in the electronic density of states (DOS). The effects of these resonant peaks on the thermoelectric properties of β -Zn4 Sb3 were analyzed. And the results showed that a ∼13/13/20-fold increase on the room-temperature Seebeck coefficient of β -Zn4 Sb3 is achieved due to Na/Li/K doping respectively. Accordingly, the optimizing power factor/thermoelectric figure of merit of β -Zn4 Sb3 gets an about 1.69/1.43-fold increase at room temperature upon Na doping. And their corresponding optimal Fermi levels of three doped compounds all lie near and below the valence band maximum of the host.