X-ray Diffraction and Fluorescence Spectroscopy Analysis of Sm3+ in Lithium Calcium Silicate

Abstract

Trivalent samarium-doped lithium calcium silicate phosphors with the nominal formulas of Li2Ca1-xSmxSiO4 were prepared with a conventional solid-state reaction technique and the dopant concentration was varied in the range of 0.01 <= x <= 0.10. The phase and structure of the as-prepared samples were characterized using X-ray diffraction. The excitation and emission spectra were measured to characterize the luminescent properties of the Li2CaSiO4:Sm3+ phosphors. The excitation and emission spectra at room temperature show the typical f-f transitions of Sm3+. The dominant excitation line is around 408 nm because of the H-6(5/2)-->K-4(11/2) transition. The emission spectrum of all phosphors exhibited four sharp emission peaks corresponding to the (4)G(5/2)-->H-6(5/2) (565 nm), (4)G(5/2)-->H-6(7/2) (601 nm) (4)G(5/2)-->H-6(9/2) (654 nm), and (4)G(5/2)-->H-6(11/2) (708 nm) transitions of Sm3+. The emission intensity depended on the Sm3+ concentration and it was observed that the optimum concentration of Sm3+ in phosphor was 4 mol% for the highest emission intensity at 601 nm.