Luminescence and energy transfer of 432 nm blue LED radiation-converting phosphor Ca4Y6O(SiO4)(6): Eu2+, Mn2+ for warm white LEDs

摘要

A series of Ca4Y6O(SiO4)(6):Eu2+, Mn2+ phosphors are synthesized by a solid state method. Ca4Y6O(SiO4)(6):Eu2+, Mn2+ can be excited at wavelength ranging from 250 to 500 nm, which is well matched with ultraviolet-visible light emitting diode. Under 432 nm excitation, Ca4Y6O(SiO4)(6):Eu2+, Mn2+ can create warm white emission by energy transfer from Eu2+ to Mn2+. A warm white light emitting diode is fabricated by combining a 432 nm blue LED with a single phase warm white emitting phosphor Ca3.92Y6O(SiO4)(6):0.05Eu(2+), 0.03Mn(2+), which has CIE chromaticity coordinates (0.336, 0.319), correlated color temperature (CCT) 4326 K and color rendering index (R-a) 86, respectively. The results indicate Ca4Y6O(SiO4)(6):Eu2+, Mn2+ may serve as potential warm white emitting phosphor for blue LED based white LEDs.