Concentration Quenching in K2SiF6:Mn4+ Phosphors

In this report, we discuss the effect of synthesis on the concentration quenching of K2SiF6:Mn4+ phosphors. Comparing two different synthesis methods, we demonstrate that Mn concentration can be increased by a factor of three before the onset of concentration quenching. These effects are analyzed using literature models for concentration quenching that show that large reductions in defect concentrations are responsible for the improvements in concentration quenching along with a possible change in the mechanism behind concentration quenching. The practical implications for LED packages using high Mn4+ concentration K2SiF6:Mn4+ phosphor with high quantum efficiencies are also discussed along with suggestions about pitfalls in the analysis of concentration quenching.