Fluorescence regulation derived from Eu3+in miscible-order fluoride-phosphate blocky phosphor.

Miscible-order fluoride-phosphate blocky phosphor, composed with ordered phase of NaYF4 crystals and unordered phase of tin-fluorophosphate glass, is prepared by a two-step process and luminescent properties of fluoride-phosphate blocky phosphors embedded with different particle sizes of NaYF4 crystals are presented. High-frequency fluorescence from higher metastable 5DJ (J = 1, 2 and 3) energy levels are effectively released in Eu3+ doped fluoride crystals. Taking the blue emission of Sn2+ as the framework, multi-peak emissions from metastable energy levels are controlled to adjust the color coordinates of the fluoride-phosphate blocky phosphor to the white-light region, which the color rendering index reaches 89. Tunable color fluoride-phosphate blocky phosphor with high color rendering index retains splendid luminescence property of fluoride, providing a potential candidate for the development of white LED.