Preparation And Luminescent Properties Of Calcium Yttrium Silicate

This paper is focused on a single phosphor Ca4Y6Si6O25, doping Eu3+, Eu2+, Ce3+and Dy3+four kinds of rare-earth ions as activators, we studied their luminescence properties in matrix and have a preliminary theoretical analysis.:Eu3+red phosphor was prepared using solid state reaction method. And the emission was mainly with 5D0 7F2 of 614nm of Eu3+. It can be used as red phosphor in "near-UV chip+tri-phosphor" and can also make up the red component in "blue chip+ yellow phosphor". The excitation spectrum of Ca4Y6Si6O25:Eu2+ green phosphor is a 350-450 nm broadband spectrum and can be well excited by near-UV to blue chip. Eu2+ takes the place of Ca2+ and occupies two kinds of lattice positions. The emission spectrum is a unsymmetrical broadband spectrum and the peak located at 527 nm. When the Eu2+ concentration is 20% intensity get to the top. According to Dexter theory, the concentration quenching is the electric quadrupole-electric quadrupole interaction. The Ce3+-doped Ca4Y6Si6O25 phosphor possesses three excitation peaks which match electron beam and UV excitation. At different excitation wavelengths, the emission spectra are also different. With the Ce3+content increased, the concentration quenching does not occur and the red shift phenomenon occurs. The color coordinates (x, y) changes from (0.1614,0.1325) to (0.1618,0.1332).Single matrix Ca4Y6Si6O25:Dy3+ material white phosphor was fabricated. This material emission spectrum peaks are located at 480 nm and 573 nm. Monitoring 480 nm and 573 nm, the excitation spectra peaks obtained basically the same as each other. The maximum excitation peak is 348 nm. When XDy=24%, Ca4Y6Si6O25:Dy3+ sample color coordinates (x, y) is (0.3011,0.3182) which is close to pure white. the concentration of quenching mechanism of Dy3+ at 573 nm electric dipole-electric dipole interaction.