The Preparation And Luminescence Properties Of Oxo-nitride Phosphors For White-light Emitting Diode(LED)

As the forth solid light source, white LED having the advantaged of energy conservation, environment protection, have earned the importance from government of every country. As the most important part, phosphor takes a huge market share. Green phosphors at present have been demanded, especially the green oxo-nitride phosphor. So whether we can produce high quality green oxo-nitride phosphor or not have a great importance. There are few kinds of blue oxo-nitride phosphors, but have great need. In this thesis, the synthesis and luminescence properties of the green phosphor BaSi2O2N2: Eu2+has been studied. A new type of blue phosphor SrAl2Si2O5N2: Eu2+has been synthesized.We have synthesized the two oxo-nitride phosphors BaSi2O2N2: Eu2+and SrAl2Si2O5N2: Eu2+by the Solid State Reaction (SSR). The structure and the luminescent properties of the samples were characterized by x ray-diffraction and spectrometer. The influence of synthetic temperature, reaction time, the concentration of alkaline earth metals and Eu2+on the luminescent properties of the samples was systematically studied.The studies show that the structure is the best under the temperature1150℃, and maintain time is3h. The best doping content of Eu2+in BaSi2O2N2: Eu2+is0.06mol%. The max absorbing peak of emitting spectra are between500nm-520nm, the peak is changing when change the content of Eu+. The emission spectrum is red shift when doping the ion Ca2+in the sample BaSi2O2N2: Eu2+, color temperature is6811K, Ra is57.42. u2+is analyzed by XRD, the result shows that the best firing temperature is1150℃, maintain time is3h, the same as BaSi2O2N2: Eu2+. The max absorbing peak of excitation spectra is between310nm-425nm, satisfying the wavelength of blue-emitting chip and ultraviolet-emitting chip. The EDS detected the presence of N, SEM shows that the crystals grow well.