A novel red phosphor for near UV InGaN light-emitting diode and its luminescent properties

A series of new red phosphors, NaEu(MoO4)2−2x(SO4)2x, were prepared by the conventional solid state reaction. Their excitation spectra, emission spectra and decay curves were measured at room temperature. When the SO42− content is in excess of 20%, other phases appear. With the introduction of SO42−, the Mo–O charge transfer band of NaEu(MoO4)2−2x(SO4)2x shows red shift, and the excitation intensities of the 4f – 4f transitions of Eu3+ are strengthened, compared with that of NaEu(MoO4)2. The single red light-emitting diodes-based these phosphors were fabricated. The light-emitting diode fabricated with the phosphor NaEu(MoO4)1.80(SO4)0.20 exhibited higher red emission relative to that with NaEu(MoO4)2. Bright red light can be observed by naked eyes from the light-emitting diode-based NaEu(MoO4)1.80(SO4)0.20.