Luminescent Properties of ${\rm Lu}_{2}{\rm SiO}_{5}{\hbox {:}}{\rm Ce}$ Phosphors Codoped With Li Ions

LSO:Ce_x, Li_y (x = 0.002-0.016 and y = 0.01-0.08) phosphors were prepared by Pechini sol-gel chemistry, and the influence of Li⁺ ions on luminescence properties of LSO:Ce phosphors was discussed. It was exhibited that the optimal doping concentrations were at x = 0.006 and y = 0.02, and the crystallization temperature of pure LSO phase was reduced distinctly by Li⁺ codoping. It was found that photoluminescence intensity of LSO:Ce_0.006 > Li_0.02 phosphors was increased by factors of 2.2 in comparison to that of LSO:Ce_0.006 phosphors. Enhanced luminescence was regarded as the result of alteration of crystal field surrounding Ce³⁺ activator. Moreover, the energy transfer from Ce2 to Cel centers was induced by Li⁺ codoping.