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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From synthesis to application: a review of BaZrS3 chalcogenide perovskites
Chalcogenide perovskites are gaining prominence as earth-abundant and non-toxic solar absorber materials, crystallizing in a distorted perovskite structure. Among these, BaZrS3 has attracted the most attention due to its optimal bandgap and its ability to be synthesized at relatively low temperatures. BaZrS3 exhibits a high light absorption coefficient, excellent stability under exposure to air, moisture, and heat, and is composed of earth-abundant elements. These properties collectively position BaZrS3 as a promising candidate for a wide range of applications, although traditional high-temperature synthesis has primarily been a significant challenge. In this review, we provide a critical discussion of the various synthesis methods employed to fabricate BaZrS3, including solid-state synthesis, nanoparticle synthesis, and vacuum-based as well as solution-based approaches to synthesize thin films. We also comprehensively examine the experimentally measured and theoretically calculated optical, optoelectronic, electronic, and defect properties of BaZrS3. Furthermore, this review highlights the functional devices based on BaZrS3, showcasing applications spanning photovoltaics, photodetection, thermoelectrics, photoelectrochemical water splitting, piezoelectricity, and spintronics. Lastly, we propose a future roadmap to maximize the potential of this material. Additionally, this review extends its focus to BaHfS3 and BaTiS3, discussing their synthesis methods, properties, and explored applications, thereby offering a comparative perspective on this emerging family of chalcogenide perovskites.
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- Award ID(s):
- 1855882
- PAR ID:
- 10657614
- Publisher / Repository:
- Nanoscale
- Date Published:
- Journal Name:
- Nanoscale
- Volume:
- 17
- Issue:
- 8
- ISSN:
- 2040-3364
- Page Range / eLocation ID:
- 4250 to 4300
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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