Structural and luminescent properties of gel-combustion synthesized green-emitting Ca3Sc2Si3O12 : Ce3+ phosphor for solid-state lighting

摘要

Ca3Sc2Si3O12 : Ce3+ phosphors with a single phase and fine size were successfully obtained at a lower temperature (1100 degrees C) using the gel-combustion method compared with the conventional solid-state reaction method (about 1500 degrees C). The crystal phase and the microstructure of the phosphors and their photoluminescence were investigated. The particle size is about 1 mu m, which is much less than that obtained by the solid-state reaction. Smaller particle size can reduce internal scattering when particles are mixed with silicon and coated onto a blue light-emitting diode (LED). A bright green emission is observed, which is attributed to the characteristic emissions from 5d-F-2(5/2) and 5d-F-2(7/2) transitions of Ce3+. The excitation spectra show a broad and strong absorption at about 460 nm, suggesting that it is very suitable for use as a colour converter in white LEDs. The decay time of the gel-combustion phosphor is 54.65 ns.