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Abstract Chalcogenide perovskites have garnered interest for applications in semiconductor devices due to their excellent predicted optoelectronic properties and stability. However, high synthesis temperatures have historically made these materials incompatible with the creation of photovoltaic devices. Here, we demonstrate the solution processed synthesis of luminescent BaZrS3and BaHfS3chalcogenide perovskite films using single‐phase molecular precursors at sulfurization temperatures of 575 °C and sulfurization times as short as one hour. These molecular precursor inks were synthesized using known carbon disulfide insertion chemistry to create Group 4 metal dithiocarbamates, and this chemistry was extended to create species, such as barium dithiocarboxylates, that have never been reported before. These findings, with added future research, have the potential to yield fully solution processed thin films of chalcogenide perovskites for various optoelectronic applications.
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Enabling Optoelectronics in Harsh Environments: Laser‐Printed Perovskite Films with Exceptional Stability Under Extreme Radiation, Thermal Stress, and Humidity
Abstract Perovskite optoelectronics are regarded as a disruptive technology, but their susceptibility to environmental degradation and reliance on toxic solvents in traditional processing methods pose significant challenges to their practical implementation. Herein, methylammonium lead iodide (MAPbI3) perovskite films processed via a solvent‐free laser printing technique, that exhibit exceptional stability, are reported. These films withstand extreme conditions, including high doses of X‐ray radiation exceeding 200 Gy, blue laser illumination, 90% relative humidity, and thermal stress up to 80 °C for over 300 min in air. We demonstrate that laser‐printed films maintain their structural integrity and optoelectronic properties even after prolonged exposure to these stressors, significantly surpassing the stability of conventionally processed films. The enhanced stability is attributed to the unique film formation mechanism and resulting defect‐tolerant microstructure. These results underscore the potential of laser printing as a scalable, safe, and sustainable manufacturing route for producing stable perovskite‐based devices with potential applications in diverse fields, ranging from renewable energy to large‐area electronics and space exploration.
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- Award ID(s):
- 2135937
- PAR ID:
- 10641556
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Energy Materials
- Volume:
- 15
- Issue:
- 16
- ISSN:
- 1614-6832
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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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.more » « less
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