Synthesis and characterization of new potassium-containing argyrodite-type compounds

Abstract

Potassium halogenthiophosphates K6PS5Br and K6PS5Cl as well as halogen-free K7PS6 compound were synthesized using the two-step technique from elemental substances as well as potassium halides. The elemental composition of the obtained samples was determined using energy-dispersive X-ray spectroscopy. Raman spectra of K6PS5Br and K6PS5Cl show themselves to be much similar to those of chemically related Cu6PS5Br and Cu6PS5Cl argyrodite crystals. The much richer spectra of K6PS5Br and K6PS5Cl as well as K7PS6, however, reveal that their structure most likely differs from the cubic structure of Cu6PS5Br and Cu6PS5Cl argyrodites.

Keywords

• argyrodite
• synthesis
• scanning electron microscopy
• raman spectroscopy