Synthesis and luminescence of sub-micron sized Ca3Sc 2Si3O12:Ce green phosphors for white light-emitting diode and field-emission display applications

摘要

Ca3Sc2Si3O12:Ce3+ phosphors with sub-micron size were successfully synthesized by a gel-combustion method. The crystal structure and morphology of the phosphors and their photoluminescence were investigated. The results indicate that the pure phase of Ca3Sc2Si3O12 can be obtained at 1100 °C of firing temperature. The particles of phosphor are basically spherical in shape with the mean size less than 1 μm. The grain of the phosphor grows up gradually with the increasing of the firing temperature. The excitation spectrum shows a broad and strong absorption band centered around 450 nm, compatible with the excited wavelength of commercial blue light-emitting diode (LED) for white LED lighting. Bright green-emission located at 505 nm is observed and the intensity of the green-emission increases with the increase of firing temperature. Additionally, under low-voltage (2.5 kV) excitation of electron beam, bright green cathodoluminescence (CL) is also observed, which is attributed to the characteristic emission from Ce3+. Our work suggests that Ca3Sc2Si3O12:Ce 3+ phosphors are promising for both white LED and field-emission display applications.