Luminescence properties of Na2SiF6: Mn4+ red phosphors for high colour-rendering white LED applications synthesized via a simple exothermic reduction reaction

Na2SiF6: Mn4+ red phosphor is reported in this paper. Na2SiF6: Mn4+ was synthesized via a simple exothermic reduction reaction approach using Na2SiF6 and NaMnO4 as raw materials. H2O2 was dropped into 0.02 mol L-1 of NaMnO4 in HF solution to reduce Mn7+ to Mn4+ at room temperature. The phosphors can produce sharp red emissions in a broad absorption range (from 500 nm to 700 nm). The white LEDs were fabricated with blue GaN chips merged with a mixture of Na2SiF6: Mn4+ and commercial YAG: Ce yellow phosphors for white light.