The Enhanced Low-Voltage Cathodoluminescent Properties of Spherical Y_2O_3:Eu~3+ Phosphors Coated with In_2O_3 and its Application to Field-Emission Displays

摘要

Dispersed and spherical Y_2O_3:Eu~3+ red phosphor particles were prepared by the urea homogeneous precipitation method. In_2O_3 nanoparticles were successfully coated on the surface of the phosphor. Phase compositions, morphologies, photoluminescence (PL) spectra, and cathodoluminescence (CL) properties of Y_2O_3:Eu~3+ phosphors before and after In2O3 coating were examined. It was found that CL properties such as luminous efficiency, lifetime, and stability of In2O3-coated phosphor screen were improved significantly, even though its PL intensity decreased compared with that of the uncoated sample. The reason is attributed to the increase of the electrical conductivity and the decrease of the charge accumulating effect. The present results prove that Y_2O_3:Eu phosphor coated with an appropriate amount of In_2O_3 is more suitable to the requirement for low-voltage field-emission displays.