Sacrificial Template Method for Fabrication of Submicrometer-Sized YPO4:Eu3+ Hierarchical Hollow Spheres

Large-scale good-quality submicrometer-sized YPO4:Eu3+ hollow spheres were synthesized by utilizing the colloidal spheres of Y(OH)CO3:Eu3+ as a sacrificial template and NH4H2PO4 as a phosphorus source, for the first time. The whole process mainly consists of the hydrothermal reaction and acid erosion. The YPO4:Eu3+-@Y(OH)CO3:Eu3+ core shell structures were first obtained after the hydrothermal process. Then, the remaining Y(OH)CO3:Eu3+ was removed by selective dissolution in a dilute nitric acid solution. The YPO4:Eu3+ hollow spheres were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and photoluminescence (PL). The formation mechanism was also investigated. The obtained YPO4:Eu3+ hollow spheres may have potential applications in cell biology, drug release, and diagnosis, due to high chemical stability and luminescence functionality.