Uniform Eu3+:CeO2 hollow microspheres formation mechanism and optical performance

Abstract The novel Eu 3+ :CeO 2 hollow microspheres are successfully fabricated by a facile and green route, employing the colloidal carbon spheres as sacrificial templates. In the coating process, the large amount of hydrophilic functional groups are beneficial to the adsorption of Ce 3+ , Eu 3+ and OH − to form the initial amorphous precursors on the surfaces of the carbon spheres. When heat-treated at appropriate temperature, the carbon spheres in the cores are burned away, while the precursors in the shell crystallize to the Eu 3+ :CeO 2 , forming a hollow structure. The Eu 3+ ions occupy the Ce sites in the CeO 2 lattice, and yield intense red emissions under 340 nm excitation. This material of hollow microspheres may find potential applications in the field of color display.