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Abstract Chalcogenide perovskites have emerged as promising semiconductor materials due to their appealing properties, including tunable bandgaps, high absorption coefficients, reasonable carrier lifetimes and mobilities, excellent chemical stability, and environmentally benign nature. However, beyond the well‐studied BaZrS3, reports on chalcogenide perovskite thin films with diverse compositions are scarce. In this study, the realization of four different types of chalcogenide perovskite thin films with controlled phases, through CS2annealing of amorphous chalcogenide precursor films deposited by pulsed laser deposition (PLD), is reported. This achievement is guided by a thorough theoretical investigation of the phase stability of chalcogenide perovskites. Upon crystallization in the distorted perovskite phase, all materials exhibit photoluminescence (PL) with peak positions in the visible range, consistent with their expected bandgap values. However, the full‐width‐at‐half‐maximum (FWHM) of the PL spectra varies significantly across these materials, ranging from 99 meV for SrHfS3to 231 meV for BaHfS3. The difference is attributed to the difference in kinetic barriers between local structural motifs for the Sr and Ba compounds. The findings underscore the promise of chalcogenide perovskite thin films as an alternative to traditional halide perovskites for optoelectronic applications, while highlighting the challenges in optimizing their synthesis and performance.
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This content will become publicly available on June 9, 2026
Spontaneous ordering in ultra-large anion size-mismatched BaZr (S1−xOx)3
Chalcogenide perovskite semiconductors, with their excellent optical absorption, chemical stability, and lack of toxicity, have emerged as a promising alternative to traditional halide perovskites. Through first-principles density functional theory, we show that despite the large lattice mismatch between the prototypical BaZrS3 and BaZrO3 chalcogenide perovskites, BaZr(S1−xOx)3 can form low-energy ordered lattices that significantly reduce strain. The bandgap dependence of the resulting ordered compound on x is found to exhibit double Vegard's law behavior, having two distinct linear regions, associated with an underlying distorted or undistorted perovskite structures.
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- PAR ID:
- 10636759
- Publisher / Repository:
- American Institute of Physics
- Date Published:
- Journal Name:
- Applied Physics Letters
- Volume:
- 126
- Issue:
- 23
- ISSN:
- 0003-6951
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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