Enhanced luminous efficiency of deep red emitting K_2SiF_6:Mn~(4+) phosphor dependent on KF ratio for warm-white LED

摘要

We demonstrate a simple method of K_2SiF_6:Mn~(4+) red phosphor and discuss its promising application in warm-white lighting emitting diodes. The K_2SiF_6:Mn~(4+) was synthesized from SiO_2 powders through redox reaction in HF/KMnO_4 solution. To further increase emission efficiency, KF was introduced in the solution. An intense absorption band in blue and a bright emission in red indicated the phosphor K_2SiF_6: Mn~(4+). This phosphor and the synthesis method are expected to be promising candidates for application in white LEDs.