Luminescent properties and energy level structure of CaZnOS:Eu2+

In this work it is shown that CaZnOS:Eu²⁺ has no Eu²⁺ emission even at low temperature. The observed and earlier reported red emission originates from a CaS:Eu²⁺ impurity phase. By means of washing the as-prepared samples with diluted nitride acid, we were able to remove the CaS impurity phase and study the...