Preparation, thermal stability, and electrical transport properties of In/Sn codoped β‐Zn₄Sb₃ single crystal

Abstract

In and Sn codoped β‐Zn4Sb3 single crystals were prepared by a Sn‐flux method according to the formula Zn4.4Sb3Sn3Inx(x = 0–0.5). The thermal weight loss is suppressed completely until the melting point of the single crystals. All crystals exhibit p‐type conduction. The carrier mobility of the single crystals is increased, compared to a β‐Zn4Sb3 polycrystalline sample. All samples possess relatively high electrical conductivity, reaching 6.3 × 104 S/m for the sample with x = 0.18. The Seebeck coefficient is enhanced on increasing of the total content of In and Sn. The sample with x = 0.5 exhibits excellent electrical properties, and shows a maximal power factor of 1.53 × 10−3 W/m/K2 at 603 K.

Thermal stability and electrical transport properties of Ge/Sn-codoped single crystalline β -Zn 4 Sb 3 prepared by the Sn-flux method

“…The highest value of 199 µV•K −1 is attained at 558 K for the x = 0.03 sample, which is comparable to previous reported values. [13,21] Then the Seebeck coefficient decreased with the increased Ge doping amount, presumably this behavior can be ascribed to the fact that the excessive Ge or the decrease of Sn have some influence on the band structure of the compounds.…”

“…[11,12] In the past years, elements in the vicinity of Zn and Sb such as In, Pb, Sn, Cd, Bi, Mg, etc. were generally selected to dope the β -Zn 4 Sb 3 , [13][14][15][16][17][18][19][20] but Ge-substitution in β -Zn 4 Sb 3 has been rarely reported so far. Wang et al recently demonstrated the realization of a high thermoelectric figure of merit in Ge-substituted β -Zn 4 Sb 3 , the experimental results and theoretical calculations revealed that Ge substitution had a marked improvement on the Seebeck coefficient and the power factor.…”