Preparation method of monodisperse silicon dioxide fluorescent microspheres

The invention discloses chemical composition and a preparation method of monodisperse silicon dioxide fluorescent microspheres. The general chemical formula of the fluorescent microspheres is SiO2@SiO2:Ln(L)3, wherein SiO2 represents silicon dioxide of the main part of the fluorescent microspheres, Ln represents a rare earth metal element serving as a luminescence center, and L represents an organic ligand serving as the enhanced fluorescence performance. The preparation method of the fluorescent microspheres is an organic ligand sensitization fluorescence enhancement-sol seed method, that is to say, silicon dioxide is taken as seed nucleuses, and a silicon dioxide-doped rare earth complex is taken as a surface coating substance. The preparation method is simple, and the obtained silicon dioxide fluorescent microspheres are good in sphericility, monodispersity, stability and luminescence property have a wide application prospect on photoelectric materials, fluorescent markers, drug targeting and the like.