The Luminescence of Nanoscale Y2Si2O7:Eu3+ Materials

The Y2Si2O7:Eu3+ sample was prepared with the sol-gel method. The Y2O3:Eu-3 was dispersed in SiO2, and the complex Y2Si2O7:Eu3+ particles were synthesized at high annealing temperature. The sample consisted of nearly spherical particles with an average size about 60 nm. The ultraviolet excitation spectra and emission spectra were measured. The sample excited by short ultraviolet light showed strongly red luminescence and fine monochromaticity. The luminescence was strongest from the D-5(0) -> F-7(2) electric dipole transition located at 611 nm. The excitation spectra of Y2Si2O7:Eu3+ excited with ultraviolet lights showed that the peak of the Eu3+-O2- charge transition band located at about 240 nm. During monitoring of different emission peaks of D-5(0) -> F-7(2), the charge transition band in the excitation spectra shifted, and the relative intensity of emission spectra changed obviously under the excitation of different ultraviolet wavelengths. These results confirmed that the Eu3+ could be excited with ultraviolet radiation of different wavelengths. At low temperature, using Eu3+ ions as fluorescence probes, we monitored the emission peaks of D-5(0) -> F-7(1) and D-5(0) -> F-7(2) transitions and measured the excitation spectra of D-7(0) -> F-5(0), D-5(0) -> F-7(1), and D-5(0) -> F-7(2) site-selective excitation spectra. These results indicated that Eu3+ ions are located in different local environments in the Y2Si2O7 host.