A single Eusup2+/sup-activated high-color-rendering oxychloride white-light phosphor for white-light-emitting diodes

摘要

A white light-emitting diode with a very high colour rendering index is made using a phosphor based on a europium-doped oxychloride material. A team of scientists from China, Switzerland and the USA investigated the white-light phosphor Sr5(PO4)3−x(BO3)xCl:Eu2+. Its structural and electronic properties were characterized by X-ray diffraction analysis, photoluminescence spectroscopy, and fluorescence decay analysis of the phosphor. When excited by ultraviolet light (365 nanometres) from a light-emitting diode, the phosphor emitted broadband photoluminescence with peaks in the blue (446 nanometres) and yellow (550 nanometres) regions. These emission characteristics resulted in high-quality white light with a very high colour rendering index that was significantly better than those of existing commercial white light-emitting diodes based on the phosphor YAG:Ce3+, indicating the potential of this new phosphor.