Chalcogenide perovskites contain sulfur, selenium, or tellurium species in place of halide anions. They could be promising non-toxic, robust semiconductors, e.g., for photovoltaics. However, they can be challenging to synthesize. There can be a high energy barrier for the crystallization of these materials, which means that generally, high temperatures (ca. 1,000 °C) and long reaction times (days to weeks) are required for their preparation.

Charles J. Hages, University of Florida, Gainesville, USA, and colleagues have developed a bottom-up, solution-based, low-temperature synthesis of chalcogenide perovskite nanoparticles, i.e., BaZrS₃ nanoparticles. The team first prepared barium dibutyldithiocarbamate (BaDBuDTC) and zirconium diethyldithiocarbamate (ZrDEtDTC) as Ba and Zr precursors. The two precursors were mixed with oleylamine (OLA), which serves as both ligand and solvent, and heated to 330 °C. After the reaction (up to 18 h), the product was isolated using a two-step centrifugation process.

Powder X-ray diffraction (XRD) and transmission electron microscopy (TEM) were used to confirm that the desired BaZrS₃ nanoparticles were obtained. The team observed promising photoluminescence properties. According to the researchers, the dithiocarbamate precursors combine low-temperature decomposition with solubility in organic solvents and also remove the need for an additional sulfur precursor. The approach could provide a path to the use of chalcogenide perovskites in thin films and devices.

• Low-Temperature, Solution-Based Synthesis of Luminescent Chalcogenide Perovskite BaZrS₃ Nanoparticles,
  Ruiquan Yang, Alexander D. Jess, Calvin Fai, Charles J. Hages,
  J. Am. Chem. Soc. 2022.
  https://doi.org/10.1021/jacs.2c06168