title: One-step large scale gas phase synthesis of Mn(2 + ) doped ZnS nanoparticles in reducing flames.
abstract: Metal sulfide nanoparticles have attracted considerable interest because of their unique semiconducting and electronic properties. In order to prepare these fascinating materials at an industrial scale, however, solvent-free, dry processes would be most advantageous. In the present work, we demonstrate how traditional oxide nanoparticle synthesis in flames can be extended to sulfides if we apply a careful control on flame gas composition and sulfur content. The ultra-fast (<1 ms) gas phase kinetics at elevated temperatures allow direct sulfidization of metals in flames ([Formula: see text]). As a representative example, we prepared air-stable Mn(2 + ) doped zinc sulfide nanoparticles. Post-sintering of the initially polycrystalline nanopowder resulted in a material of high crystallinity and improved photoluminescence. An analysis of the thermodynamics, gas composition, and kinetics in these reducing flames indicates that the here-presented extension of flame synthesis provides access to a broad range of metal sulfide nanoparticles and offers an alternative to non-oxide phosphor preparation.
authors.affiliation: Institute for Chemical and Bioengineering, ETH Zurich, Zurich, CH-8093, Switzerland.
authors.forename: E K
authors.initials: EK
authors.lastname: Athanassiou
authors.forename: R N
authors.initials: RN
authors.lastname: Grass
authors.forename: W J
authors.initials: WJ
authors.lastname: Stark