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.
Chalcogenide perovskites are promising semiconductor materials with attractive optoelectronic properties and appreciable stability, making them enticing candidates for photovoltaics and related electronic applications. Traditional synthesis methods for these materials have long suffered from high‐temperature requirements of 800–1000 °C. However, the recently developed solution processing route provides a way to circumvent this. By utilizing barium thiolate and ZrH2, this method is capable of synthesizing BaZrS3perovskite at modest temperatures (500–600 °C), generating crystalline domains on the order of hundreds of nanometers in size. Herein, a systematic study of this solution processing route is done to gain a mechanistic understanding of the process and to supplement the development of device quality fabrication methodologies. A barium polysulfide liquid flux is identified as playing a key role in the rapid synthesis of large‐grain BaZrS3perovskite at modest temperatures. Additionally, this mechanism is successfully extended to the related BaHfS3perovskite. The reported findings identify viable precursors, key temperature regimes, and reaction conditions that are likely to enable the large‐grain chalcogenide perovskite growth, essential toward the formation of device‐quality thin films.
- NSF-PAR ID:
- 10418666
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Energy and Sustainability Research
- Volume:
- 4
- Issue:
- 5
- ISSN:
- 2699-9412
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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