Title

Expanding the I-II-V Phase Space: Soft Synthesis of Polytypic Ternary and Binary Zinc Antimonides

Publication Date

8-13-2018

Department

Ames Laboratory; Chemistry

Campus Units

Ames Laboratory, Chemistry

OSTI ID+

1477244

Report Number

IS-J 9738

DOI

10.1021/acs.chemmater.8b02910

Journal Title

Chemistry of Materials

Volume Number

30

Issue Number

17

First Page

6173

Last Page

6182

Abstract

Soft chemistry methods offer the possibility of synthesizing metastable and kinetic products that cannot be obtained through thermodynamically controlled, high-temperature reactions. A recent solution-phase exploration of Li–Zn–Sb phase space revealed a previously unknown cubic half-Heusler MgAgAs-type LiZnSb polytype. Interestingly, this new cubic phase was calculated to be the most thermodynamically stable, despite prior literature reporting only two other ternary phases (the hexagonal LiGaGe-type LiZnSb and the cubic full-Heusler Li2ZnSb). This surprising discovery, coupled with the intriguing optoelectronic and transport properties of many antimony-containing Zintl phases, required a thorough exploration of synthetic parameters. Here, we systematically study the effects that different precursor concentrations, injection order, nucleation and growth temperatures, and reaction time have on the solution-phase synthesis of these materials. By doing so, we identify conditions that selectively yield several unique ternary (c-LiZnSb vs h*-LiZnSb), binary (ZnSb vs Zn8Sb7), and metallic (Zn and Sb) products. Further, we find one of the ternary phases adopts a variant of the previously observed hexagonal LiZnSb structure. Our results demonstrate the utility of low-temperature solution-phase—soft synthesis—methods in accessing and mining a rich phase space. We anticipate that this work will motivate further exploration of multinary I–II–V compounds and encourage similarly thorough investigations of related Zintl systems by solution-phase methods

DOE Contract Number(s)

AC02-07CH11358

Language

en

Department of Energy Subject Categories

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY

Publisher

Iowa State University Digital Repository, Ames IA (United States)

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