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Chalcogenide perovskites represent a prominent class of emerging semiconductor materials for photovoltaic applications, boasting excellent optoelectronic properties, appropriate bandgaps, and remarkable stability. Among these, BaZrS3 is one of the most extensively studied chalcogenide perovskites. However, its synthesis typically demands high temperatures exceeding 900 °C. While recent advancements in solution-processing techniques have mitigated this challenge, they often rely on costly and difficult-to-find organometallic precursors. Furthermore, there is a notable gap in research regarding the influence of the Ba/Zr ratio on phase purity. Thus, our study explores solid-state reactions to investigate the impact of metal ratios and sulfur pressure on the phase purity of BaZrS3. Expanding upon this investigation, we aim to leverage cost-effective metal halide and metal sulfide precursors for the solution-based synthesis of BaMS3 (M=Ti, Zr, Hf) compounds. Additionally, we have devised a bilayer stacking approach to address the halide affinity of alkaline earth metals. Moreover, we introduce a novel solution-chemistry capable of dissolving alkaline earth metal sulfides, enabling the synthesis of BaMS3 compounds from metal sulfide precursors. While the BaSx liquid flux has shown promise, we identify the selenium liquid flux as an alternative method for synthesizing BaMS3 compounds.
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Quantitative Scales for Haliphilicity of Metals: Tailoring the Halide Affinity of Alkaline Earth Metals to Synthesize Chalcogenide Perovskite BaMS3 (M = Zr, and Hf) and Cu2BaSnS4 Compounds
Chalcogenide semiconductors, such as BaMS3 (M = Zr and Hf) and Cu2BaSnS4, have attracted growing interest due to the constituent elements’ abundance and reported promising properties. However, the synthesis of these alkaline earth-containing chalcogenides from commonly available metal halides has generally been unsuccessful and has traditionally relied on expensive organometallic precursors or vacuum processing techniques, which hinder widespread research on these materials. In this study, we conducted thermodynamic calculations and developed chloriphilicity and iodiphilicity scales for various metals, leveraging their relative affinities for chlorine and iodine, respectively, compared to their corresponding metal sulfides. Utilizing these scales, we introduced a K2S–H2S system to address the affinity of alkaline earth metals for chlorine and iodine. This approach enables the synthesis of these intriguing chalcogenide materials through solution-based methods using metal chloride and metal iodide precursors. This system demonstrates remarkable efficacy for both sulfide and selenide semiconductors.
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- Award ID(s):
- 1855882
- PAR ID:
- 10657615
- Publisher / Repository:
- ACS Publications
- Date Published:
- Journal Name:
- ACS Applied Energy Materials
- Volume:
- 7
- Issue:
- 22
- ISSN:
- 2574-0962
- Page Range / eLocation ID:
- 10584 to 10595
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1021/acsaem.4c02205
