Improvement in durability of red phosphor encapsulated by sol-gel glass for use in white light-emitting diode

Abstract

Transparent glass films with homogeneously doped light emissive molecules can be prepared by using the sol-gel process. As part of our work on improving the durability of water-soluble polysilanes against UV light irradiation we fabricated Eu(TTA)3Phen-doped sol-gel glasses and studied their optical characteristics. Using a three dimensional dense glass network protects the Eu complex from free oxygen and water in an ambient and also improves the durability without any loss of light output. By adding the Eu(TTA)3Phen beyond the limit of solubility in a starting solution, we demonstrated that the glass encapsulation prevents oxidation of the Eu-complex and also preserves its excitation intensity at a wavelength of 400 nm.