Facile Preparation Method for Rare Earth Phosphate Hollow Spheres and Their Photoluminescence Properties

We have developed a template-free hydrothermal method of constructing rare earth phosphate hollow spheres using H<sub>6</sub>P<sub>4</sub>O<sub>13</sub> as the PO<sub>4</sub><sup>3−</sup> source. The mechanism of hollow spheres formation was proposed on the basis of Ostwald ripening. The resulting hollow spheres, especially with the aid of doping of other lanthanide cations, exhibit emission spanning the whole UV−visible wavelength range.