A broadband yellow-green emitting mixed orthoborate-pyroborate phosphor, Ba 2 Sc 2 B 4 O 11 :Ce 3+ , for white light emitting diodes.

The development of yellow-green phosphors for high quality white light emitting diodes (WLEDs) is critical. Herein, we successfully synthesized a mixed orthoborate-pyroborate phosphor, Ba 2 Sc 2 B 4 O 11 :Ce 3+ , using a high-temperature solid-state method, which exhibits bright yellow-green emission with a peak located at 540 nm and a full width at half maximum (FWHM) of 130 nm under 410 nm light excitation. In addition, the crystal structure, morphology, and thermal quenching properties of Ba 2 Sc 2 B 4 O 11 :Ce 3+ were investigated in detail. The quantum yield of the optimal sample was found to be 53.3%. The concentration quenching occurred through the energy transition between the nearest-neighbor Ce 3+ ions. A WLED with a low correlated color temperature (CCT = 3906 K) and a high color rendering index ( R a = 89) was prepared by coating the mixture of the phosphor Ba 2 Sc 2 B 4 O 11 :Ce 3+ , the commercial blue phosphor BaMgAl 10 O 17 :Eu 2+ and the red phosphor CaAlSiN 3 :Eu 2+ on a 395 nm n-UV LED chip. The results show that the yellow-green phosphor Ba 2 Sc 2 B 4 O 11 :Ce 3+ could be an excellent candidate for WLEDs.