Increased Synthetic Control—Gaining Access to Predicted Mg₂Si₅N₈ and β‐Ca₂Si₅N₈

Abstract

Abstract Nitridosilicates represent an intriguing class of materials and are typically made up of highly condensed tetrahedral network structures. Alkaline‐earth nitridosilicates emerged as unique host materials for Eu 2+ doped luminophores which found broad application in phosphor‐converted (pc)‐LEDs. In contrast to common strategies of preparing nitridosilicates by bottom‐up syntheses, we have now succeeded to post‐synthetically design nitridosilicates by ion exchange in metal halide melts. We describe the syntheses of hitherto unknown but predicted alkaline‐earth nitridosilicates, Mg 2 Si 5 N 8 and β‐Ca 2 Si 5 N 8 . Both compounds were obtained by ion exchange starting from pre‐synthesized nitridosilicates. In situ investigations of the ion‐exchange process show that the Si–N network topology remains preserved. Therefore the reaction offers a significant increase of synthetic control with respect to classical bottom‐up syntheses.