title: Unexpected high-temperature stability of β-Zn4Sb3 opens the door to enhanced thermoelectric performance.
abstract: β-Zn4Sb3 has one of the highest ZT reported for binary compounds, but its practical applications have been hindered by a reported poor stability. Here we report the fabrication of nearly dense single-phase β-Zn4Sb3 and a study of its thermoelectric transport coefficients across a wide temperature range. Around 425 K we find an abrupt decrease of its thermal conductivity. Past this point, Zn atoms can migrate from crystalline sites to interstitial positions; β-Zn4Sb3 becomes metastable and gradually decomposes into Zn(hcp) and ZnSb. However, above 565 K it recovers its stability; in fact, the damage caused by decomposition can be repaired completely. This is key to its excellent thermoelectric performance at high temperature: the maximum ZT reaches 1.4. Molecular dynamics simulations are used to shed light on the microscopic behavior of the material.
authors.affiliation: State Key Laboratory for Mechanical Behavior of Materials and ‡Frontier Institute of Science and Technology, Xi'an Jiaotong University , Xi'an, 710049, P. R. China.
authors.forename: Jianping
authors.initials: J
authors.lastname: Lin
authors.forename: Xudong
authors.initials: X
authors.lastname: Li
authors.forename: Guanjun
authors.initials: G
authors.lastname: Qiao
authors.forename: Zhao
authors.initials: Z
authors.lastname: Wang
authors.forename: Jesús
authors.initials: J
authors.lastname: Carrete
authors.forename: Yang
authors.initials: Y
authors.lastname: Ren
authors.forename: Lingzhi
authors.initials: L
authors.lastname: Ma
authors.forename: Youjian
authors.initials: Y
authors.lastname: Fei
authors.forename: Baifeng
authors.initials: B
authors.lastname: Yang
authors.forename: Lei
authors.initials: L
authors.lastname: Lei
authors.forename: Ju
authors.initials: J
authors.lastname: Li