The Preparation And Luminescence Properties Of Ca₁₀Li（PO₄）₇doped With Rare Earth Ions

A novel Ca10Li(PO4)7phosphors doped with Sm3+, Eu3+, Tb3+and Dy3+was prepared bysolid state reaction method at1050℃4h. we discussed several aspects research of the fourkind rare earth ions in different chapters, such as the XRD results, the excitation spectra, theemission spectra, the influence of the concentration and other luminous performance. And thespecific contents as follows:(1) The excitation spectra of the red phosphors Ca10Li(PO4)7: Sm3+were located at362,376,404and477nm, originated from the6H5/25P5/2,6H5/24L7/2,6H5/24F7/2,6H5/24I11/2transition. The strongest excitation peak was located at404nm. The emission spectra of thered phosphors were located at565,605,651and711nm, originated from the4G5/2�'6H5/2,4G5/2�'6H7/2,4G5/2�'6H9/2,4G5/2�'6H11/2transition. The strongest emission peak was located at605nm.(2) The excitation spectra of the phosphor Ca10Li(PO4)7: Eu3+was located from nearultraviolet to blue region. The strongest excitation peaks were located at394nm and465nmrespectivly. The sample could be excited by NUV-LED and blue LED. Under the irradiationof394nm near-ultraviolet (NUV) light, the spectra of the phosphors showed a main emissionpeak at618nm attributed to the5D0�'7F2transition of Eu3+ions. The color of the phosphorwas red.(3) The emission spectra of Ca10Li(PO4)7: Tb3+phosphors exhibited two groups peaksassigned to the5D37Fi(i=6,5,4) and5D47Fj(j=6,5,4,3) transitions of Tb3+under225nmexciation. The strongest emission peak was located at547nm. The concentration quenches ofthe two groups peaks were6%,18%respectively. The energy transfer of Ce3+Tb3+wasstudied. With the increase of Tb3+concentration, Ce3+to Tb3+energy transfer efficiency andthe luminous intensity of the samples increased gradually. Furthermore, the phosphors couldgenerate light from blue through green-blue and eventually to green by properly tuning therelative ratio of Ce3+to Tb3+ions grounded on the principle of energy transfer.(4) The main excitation peaks of Ca10Li(PO4)7:Dy3+were located at349nm (6H15/2�'6P7/2),363nm (6H15/2�'6P5/2) and385nm (6H15/2�'6M21/2). The sample could beexcited by UV-LED. The emission spectrum was composed of two peaks, which were locatedat481nm (blue) and572nm (yellow), corresponding to the4F9/2�'6H15/2、6H13/2typicaltransition of Dy3+. The quenching concentration was10%. The intensities increased with theincreasing of Ce3+concentration. The relative intensity of the sample reached the maximumvalue when Dy3+concentration was10%, Ce3+concentration was14%. The color of thephosphor was changed from yellow-white to blue-white.