A single red InGaN-based light-emitting diode with a europium (III) ternary complex as mono-phosphor.

ABSTRACT

A novel europium (III) ternary complex, Eu(TPBDTFA)(3)Phen, was designed and synthesized. Photoluminescence measurements show that the energy absorbed by the organic ligands was efficiently transferred to the central Eu(3+) ions, and the complex exhibits strongly red emission due to the (5)D(0)-(7)F(j) transitions of Eu(3+) ions with appropriate CIE (Commission Internationale de l'Eclairage, International Commission on Illumination) chromaticity coordinates (x=0.66, y=0.33) under 310-420 nm light excitation. The luminescence quantum yield for the Eu(3+) complex is 0.18. Thermogravimetric analysis (TGA) confirms a high thermal stability of the complex with a decomposition temperature of 341 degrees C. All the characteristics indicate that the Eu(3+) complex is a highly efficient red phosphor suitable to be excited by near UV light. An intense red-emitting LED was fabricated by combining the mono-phosphor Eu(TPBDTFA)(3)Phen with a approximately 395 nm emitting InGaN chip.