Organic solvent-assisted synthesis of the K3SiF7:Mn4+ red phosphor with improved morphology and stability

• Published in: Journal of materials chemistry. C, Materials for optical and electronic devices Vol. 7; no. 47; pp. 15014 - 15020
• Main Authors: Noh, Minhee, Dae Ho Yoon, Chang Hae Kim, Lee, Seon Joo
• Format: Journal Article
• Language: English
• Published: Cambridge Royal Society of Chemistry 01.01.2019
• Subjects: Alkali metals; Chemical synthesis; Chromaticity; Functional groups; Germanium; High temperature; Ions; Manganese ions; Morphology; Organic chemistry; Phosphors; Silicon; Solvents; Stability; Zirconium
• ISSN: 2050-7526; 2050-7534
• DOI: 10.1039/c9tc04670d

Recently, a novel host, K3SiF7, for Mn4+-activated phosphors was discovered and it was revealed that Mn4+-doped K3SiF7 has an advantage in decay time compared with the most widely used Mn4+-doped K2SiF6. Here, we developed an organic solvent-assisted synthetic method for the K3SiF7:Mn4+ phosphor. To the best of our knowledge, it is the first publication about a newly developed synthetic method of the K3SiF7:Mn4+ phosphor. Various organic solvents with different functional groups have been tried to synthesize the K3SiF7:Mn4+ phosphor. When we introduced oleylamine (OAm) as an organic solvent, uniform K3SiF7:Mn4+ particles below 5 μm were obtained at a lower temperature than the conventional solid state reaction (SSR). As a result of thermal quenching (TQ) and 85/85 tests, it was confirmed that despite its small size, the resulting K3SiF7:Mn4+ has enhanced stability against heat and moisture with the aid of an organic protecting layer. We expect that this organic solvent-assisted synthesis can be applied to the synthesis of other phosphors with a chemical formula of A3MF7:Mn4+ (A = alkali metal ion; M = Si, Ge, Zr, etc.).