Ca2MgSi2O7: Eu2+, Dy3+ long afterglow lurninescent powder was prepared by sol-gel method using tetraethylorthosilicate and nitrate as the raw materials. The preparing conditions of the precursor were determined. The powder was characterized by X-ray diffraction. The results show that transparent and homogeneous sol and gel can be prepared at pH = 1 similar to 3, R >= 4, t >= room temperature, controlling dosage of solvent. The precursor prepared at R = 12, pH= 3, t=50 degrees C is sintered to form Ca2MgSi2O7: Eu2+, Dy3+ afterglow luminescent powder at 1100 degrees C for 3 h. The powder has photoluminescence and long afterglow luminescent behavior and gives out yellow-green lower luminance long afterglow whose luminescent persistence time lasts about 1 h. There is lower intensity excitation band at 340-480 nm on its excitation spectrum and emission peak on its emission spectrum is at 528 nm.
