Alkali Metal Hexafluorido Plumbates(IV) A2[PbF6] (A=Na−Cs) and Luminescence of the Mn4+‐substituted Compounds A2[PbF6] : Mn (A=Li−Cs) and Li2[MF6] : Mn (M=Ti, Ge, Sn)

• Published in: European journal of inorganic chemistry 2021-10, Vol.2021 (37), p.3870-3877
• Main Authors: Bandemehr, Jascha, Baumann, Dominik, Seibald, Markus, Kraus, Florian
• Format: Article
• Language: English
• Subjects: Alkali metals; Cesium; Crystal structure; Crystals; Emitters; Fluorides; Fluorination; Germanium; Hydrofluoric acid; Infrared spectroscopy; Inorganic chemistry; LEDs; Lithium; Luminescence; Phosphors; Structure elucidation; Substitutes; Synthesis; Tin; Titanium
• ISSN: 1434-1948; 1099-0682
• DOI: 10.1002/ejic.202100577

We synthesized eight novel red‐emitting Mn4+‐substituted phosphors of the compositions A2[PbF6] : Mn (A=Li−Cs) and Li2[MF6] : Mn (M=Ti, Ge, Sn) using a dry‐chemical fluorination process which completely avoids the usage of hydrofluoric acid. Compared with the commonly used red‐emitter K2[SiF6] : Mn (KSF) the two synthesized phosphors Na2[PbF6] : Mn and Li2[GeF6] : Mn show a blue‐shift of their emission maximum, Na2[PbF6] : Mn even by 4.2 nm. The compounds were characterized by powder X‐ray diffraction, IR and emission spectroscopy. Additionally, we present the crystal structures of the unsubstituted compounds A2[PbF6] (A=Na−Cs). Na2[PbF6] crystallizes in the trirutile structure type, whereas the other three are isotypic to K2[GeF6] (space group P3‾m ). Eight novel red‐emitting Mn4+‐substituted phosphors of the compositions A2[PbF6] : Mn (A=Li−Cs) and Li2[MF6] : Mn (M=Ti, Ge, Sn) were synthesized using a dry‐chemical fluorination process which completely avoids the usage of hydrofluoric acid. In comparison to the state of the art red‐emitter K2[SiF6] : Mn (KSF) the phosphors Na2[PbF6] : Mn and Li2[GeF6] : Mn show a blue‐shift of their emission maximum.