Color tunability imparted by multi-peak emissions of Eu3+ in fluoride-phosphate phosphors

Abstract

Miscible-order NaGdF4 fluoride-phosphate phosphor has been synthesized based on tin-fluorophosphate glass with low-melting-point, retaining excellent luminescence property of fluoride nanoparticles. Multi-peak emissions from metastable 5DJ (J = 0, 1, 2 and 3) levels are released effectively in the Eu3+ doped fluoride nanoparticles, which lifetimes are at the order of millisecond and quantum efficiency at 5D0 level in high Eu3+ concentration still remains 88.9%. On the basis of multi-peak emissions from Eu3+ and wide-band blue framework from Sn2+, the color coordinates of the fluoride-phosphate phosphors are regulated to the white light region and the color rendering index reaches up to 88. Tunable color and high color rendering index make fluoride-phosphate phosphor become a potential candidate for high-quality white light source.