Controllable synthesis of glass ceramics containing YF3:Eu3+ nanocrystals: Well‐preserved Eu and prolonged lifetime.

Monolithic luminescent glass‐ceramic (GC) embedded with fluoride‐based nanocrystals (NCs) has drawn much attention as it is stable and possesses long fluorescent lifetime, while only small partial of optically active ions could enter the fluoride NCs prepared by conventional crystallization process. In this work, YF3:Eu3+ embedded GCs have been controllably synthesized by Spark Plasma Sintering at a relatively low sintering temperature (960°C) within 10 minutes. The GC samples show typical sharp reddish‐orange emissions peaking at λ = 590 nm and 620 nm, which can be ascribed to the 5D0 → 7Fj transitions of Eu3+ located in the tetrahedral coordination sites of the YF3 NCs. Significantly, a small R/O ratio (photoluminescence intensity ratio of 5D0 → 7F2/5D0 → 7F1) suggests that majority of Eu3+ ions are well preserved in YF3 NCs, which is confirmed by the EDS and TEM results that highly crystallized YF3:Eu3+ NCs are homogeneously dispersed into the silica glass matrix without interfacial reaction. Hence, the lifetime of GC sample is prolonged to 6.8 ms These results demonstrate that Eu3+ could be well protected and resided in YF3 low phonon crystal by this method to fabricate GC composites with high optical performance. [ABSTRACT FROM AUTHOR]