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Chalcogenide perovskites have recently attracted significant attention for renewable energy applications due to their predicted combination of air, moisture, and thermal stability, which has been experimentally validated, along with their excellent optoelectronic properties, which are still under experimental investigation. While historically requiring high synthesis temperatures, some solution-processed routes have recently emerged for synthesizing chalcogenide perovskites, such as BaZrS3 and BaHfS3, at temperatures below 600 °C. This study discusses several experimental challenges associated with the moderate-temperature synthesis of solution-deposited chalcogenide perovskites. Firstly, we identify Ruddlesden–Popper (RP) phases as thermodynamically stable competing secondary phases in perovskite synthesis. High sulfur pressures favor the formation of BaZrS3 or BaHfS3, whereas lower sulfur pressures result in a mixture of perovskite and RP phases. Additionally, we briefly discuss the mechanism of moderate-temperature synthesis of chalcogenide perovskites, including some of the morphological and optoelectronic challenges it presents, such as grain overgrowth, secondary phase contamination entrapment, and the presence of mid-band gap emissions. Finally, we address the importance of substrate selection and the potential presence of Ca- and Na-based impurities originating from cation out-diffusion from glass substrates. Addressing these challenges will be crucial as these unique materials continue to be investigated for applications in optoelectronic devices.
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This content will become publicly available on September 2, 2026
Moderate-temperature solution-processed synthesis of incommensurate Sr8/7TiS3 thin films and rod-shaped nanocrystals
The chalcogenide perovskite family has been steadily gaining increasing attention from the research community due to its optoelectronic properties and potential for diverse applications. While BaZrS3 and BaTiS3 have been the most extensively studied, other promising compounds in this family, such as SrxTiS3 (1.05 < x < 1.22), are now being explored for various optical, optoelectronic, and energy storage applications. However, challenges remain in achieving the low-temperature synthesis of SrxTiS3. In this study, we report, for the first time, the synthesis of SrxTiS3 nanocrystals at temperatures below 400 °C. The synthesized nanocrystals exhibit a rod-like morphology. Additionally, we have developed solution-processing routes to synthesize phase-pure SrxTiS3 thin films, marking the first reported instance of such films, at temperatures below 600 °C. We also demonstrate the solid-state synthesis of SrxTiS3 powder below 600 °C. Our work paves the way for new and exciting application avenues for SrxTiS3.
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- Award ID(s):
- 2422591
- PAR ID:
- 10657611
- Publisher / Repository:
- Journal of Materials Chemistry C
- Date Published:
- Journal Name:
- Journal of Materials Chemistry C
- Volume:
- 13
- Issue:
- 38
- ISSN:
- 2050-7526
- Page Range / eLocation ID:
- 19699 to 19711
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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