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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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Enhanced photoresponse in BaZrS3 thin films via sputtering and flux-assisted sulfurization
Abstract Chalcogenide perovskites, particularly BaZrS3, hold promise for optoelectronic devices owing to their exceptional light absorption and inherent stability. However, thin films obtained at lower processing temperatures typically result in small grain sizes and inferior transport properties. Here we introduce an approach employing co-sputtering elemental Ba and Zr targets followed by CS2sulfurization, with a judiciously applied NaF capping layer. NaF acts as a flux agent during sulfurization, leading to marked increase in grain size and improved crystallinity. This process results in near-stoichiometric films with enhanced photoresponse. Terahertz spectroscopy further reveals a carrier mobility more than two orders of magnitude higher than those obtained from field-effect transistor measurements, suggesting that bulk transport is limited by grain boundary scattering. Our results demonstrate flux-assisted sulfurization as an effective strategy to improve the crystallinity of chalcogenide perovskite thin films for optoelectronic applications. Graphical abstract
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- PAR ID:
- 10633286
- Publisher / Repository:
- Cambridge University Press (CUP)
- Date Published:
- Journal Name:
- Journal of Materials Research
- Volume:
- 40
- Issue:
- 17
- ISSN:
- 0884-2914
- Format(s):
- Medium: X Size: p. 2566-2574
- Size(s):
- p. 2566-2574
- Sponsoring Org:
- National Science Foundation
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