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

Abstract

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.