Tunable single-phased white-emitting phosphors Na3YSi3O9:Tm3+, Dy3+

A single-phased Na3YSi3O9:Tm3+, Dy3+ phosphors was prepared by solid-phase reaction. X-ray diffraction and photoluminescence spectrum were used to investigate their structure and optical properties, respectively. Tm3+ and Dy3+ ions were introduced as blue and yellowish-green activators into Na3YSi3O9 lattice, respectively. Under ultraviolet excitation, the emission colors of the Na3YSi3O9:xTm3+, (0.03−x)Dy3+ phosphors can be tuned from warm white to cool white and ultimately to yellowish-green through controlling the Tm3+ concentration within 0≤x≤0.03. A white-emitting phosphor Na3YSi3O9:0.01Tm3+, 0.02Dy3+ was achieved with chromaticity coordinates of (0.3117, 0.3250) and correlated color temperature of 6592 K. This is very close to the CIE Illuminant D65 ((0.3127, 0.3290), 6504 K), which is a standard illuminant for the European Broadcasting Union (EBU) primary system colors. All the results indicate that the phosphors can potentially be used for white light emitting diodes.