Synthesis, morphology, photoluminescence and photocatalytic properties of yolk-shell Au@Y2O3:Eu3+ sub-microspheres

Uniform yolk-shell Au@Y2O3:Eu3+ sub-microsphere phosphors were successfully prepared through urea-assisted homogeneous precipitation method by using carbon spheres as templates. The structure, morphology, photoluminescence and photocatalytic properties of the as-prepared Au@Y2O3:Eu3+ microspheres were subsequently investigated. The results indicate that the Y2O3:Eu3+ microspheres can be well indexed to the cubic Y2O3 phase. Furthermore, the Au@Y2O3:Eu3+ microsphere is able to maintain the spherical morphology and good dispersion of the carbon sphere template. The yolk-shell Au@Y2O3:Eu3+ spheres exhibit the bright luminescence of Eu3+. The photocatalysis of the Y2O3:Eu3+ shell and the Au core occur simultaneously, thereby significantly decreasing the absorbance of rhodamine B solutions. This work provides a strategy for inhibiting aggregation of noble metal nanoparticles during high-temperature calcinations and leaching of noble metal nanoparticles into a solution through a mesoporous shell. Ultimately, a multifunctional nanostructure was obtained by combining a specific metal core with an oxide shell.