Comparative investigation on solvent-related morphology and luminescence properties of a novel red phosphor NaRbSnF6:Mn4+ for WLEDs application

Abstract A novel red phosphor NaRbSnF6:Mn4+ (NRSF:Mn) with narrow band red-emitting peaks and broad absorption band in blue region has been synthesized by an ion-exchange method at room temperature, and the formation mechanism has been investigated by varying the molecular rations of starting materials. The morphology and luminescence properties of NRSF:Mn are strongly dependent on the solvents utilized in synthetic process, such as acetone, methanoic acid, ethylalcohol, and ethyl glycol. The viscosity and volume fraction of the solvents play crucial roles on the yield and the luminescence efficiency of the phosphor NRSF:Mn. The luminescence efficiency has been enhanced by optimizing the synthetic parameters, such as the volume fraction of the solvents and the doping concentration of [MnF6]2-. The decomposition temperature of NRSF:Mn is as high as 730 °C and its color purity is 98%. The outstanding thermal stability and high color purity of NRSF:Mn make it have great potential applications in warm white light-emitting diodes (WLEDs). The advantage of the strategy to optimizing the yield and luminescence efficiency of the phosphor NRSF:Mn can be extended to developing Mn4+ doped red phosphors for large scale industrial applications.