Rhodamine 6G Dye Encapsulated Mesoporous SiO2/SrAl2O4:Eu2+, Dy3+ Composite Yellow Long Persistent Phosphor

Abstract

A novel rhodamine 6G dye encapsulated mesoporous SiO2/SrAl2O4:Eu2+, Dy3+ composite yellow long lasting phosphor was prepared based on the color conversion process. The color conversion was achieved by mixing rhodamine 6G dye encapsulated mesoporous silica nanoparticles (MSNp-Rh6G) with SrAl2O4:Eu2+, Dy3+ (SAO) long persistent phosphor in a mass ratio. The X-ray diffraction, Field Emission Scanning Microscopy, Transmission Electron Microscopy, photoluminescence, phosphorescence, and decay curve were utilized to characterize the composite phosphor. The photoluminescence emission spectrum of SAO is overlapped with the excitation spectrum of MSNp-Rh6G which indicates the rhodamine 6G dye encapsulated mesoporous silica nanoparticles can be excited by the phosphorescence emission of SAO. The phosphorescence emission of the composite long persistent phosphor can be tuned from green to yellow by changing the mass ratio of MSNp-Rh6G/SAO. A yellow phosphorescence emission was achieved with color co-ordinates (0.40, 0.50). The decay curves of the composite MSNp-Rh6G/SAO phosphor shows that the decay due to the peak of SAO and MSNp-Rh6G has similar decay kinetics which indicates the constant and steady color during decay process. The detailed color conversion process is described here. The results indicate that the composite LLP can be potentially applicable as a new long lasting phosphor used in the field of emergency light, display, luminous paint.