High Eu concentration quenching in YTaO solid solution for orange-reddish emission in photonics.

We report the synthesis of a YTaO solid solution containing a high Eu concentration (from 7 up to 50 mol%) and investigate how Eu influences the YTaO crystallization process. To this end, we evaluate the YTaO structural features and photoluminescence properties after Eu introduction into the YTaO lattice. The higher the Eu ion concentration, the more stable the crystallization process of the YTaO phase seems to be. The Eu-containing YTaO displays intense orange-reddish, broad band emission because Eu occupies different symmetry sites in the host and causes inhomogeneous broadening. Eu emission quenching due to Eu concentration is negligible up to 30 mol% and absolute quantum yield values of up to nearly 30% were obtained, making Eu-containing YTaO interesting materials for application as high-intensity emitters in photonics.