(358f) A Low-Temperature Growth Mechanism for Chalcogenide Perovskites | AIChE

(358f) A Low-Temperature Growth Mechanism for Chalcogenide Perovskites


Yang, R. - Presenter, University of Florida
Fai, C., University of Florida
Chase, W. J., University of Florida
Tervil, M. P., University of Florida
Jess, A., Texas A&M University-Kingsville
Nelson, J., University of Tennessee, Knoxville
Hages, C., University of Florida
Chalcogenide perovskites have attracted increasing research attention in recent years due to their promise of unique optoelectronic properties combined with stability. However, the synthesis and processing of these materials has been constrained by the need for high temperatures and/or long reaction times. As a representative of chalcogenide perovskites, BaZrS3 has been mainly synthesized by (1) heating BaS and ZrS2; (2) sulfurizing BaZrO3 and elemental powders; (3) post sulfurization of co-sputtered Ba-Zr-O/S film, all of which require high temperatures and/or long reaction times. Recently, BaS3 has been hypothesized to be a liquid flux that has potential to reduce the reaction temperature and shorten the reaction time for BaZrS3 formation considerably.

In this work, we address the open question of a low-temperature growth mechanism for BaZrS3. Ultimately, a liquid-assisted growth mechanism for BaZrS3 using molten BaS3 as a flux is demonstrated at temperatures ≥ 540 oC in as little as 5 minutes. The role of Zr-precursor reactivity and 𝑆(𝑔.) on the growth mechanism and formation of Ba3Zr2S7 is discussed, in addition to the purification of resulting products using a straightforward H2O wash. The extension of this growth mechanism is shown for other Ba-based chalcogenides, including BaHfS3, BaNbS3, and BaTiS3. In addition, an alternative vapor-transport growth mechanism is presented using S2Cl2 for the growth of BaZrS3 at temperatures as low as 500 oC in at least 3 h. These results demonstrate the feasibility of scalable processing for the formation of chalcogenide perovskite thin films.