Chemistry, Ames Laboratory
Journal or Book Title
Journal of the American Chemical Society
The first example of polytypism in the I–II–V semiconductors has been demonstrated with the synthesis of cubic LiZnSb by a low-temperature solution-phase method. This phase exhibits a unique coloring pattern that is novel for this class of compounds. The choice of site configuration has a considerable impact on the band structure of these materials, which in turn affects the transport properties. While the hexagonal polytype has been suggested as a promising n-type and extremely poor p-type thermoelectric material, the cubic analogue is calculated to have high efficiencies for both the n- and p-type derivatives (1.64 and 1.43, respectively, at 600 K). Furthermore, the cubic phase is found to be the energetically favored polytype. This surprising result provides a rationale for the lack of success in synthesizing the hexagonal polytype in either stoichiometric or n-type compositions.
American Chemical Society
White, Miles A.; Miller, Gordon J.; and Vela, Javier, "Polytypism and Unique Site Preference in LiZnSb: A Superior Thermoelectric Reveals Its True Colors" (2016). Chemistry Publications. 952.