Hollow TiO2:Sm3+ spheres with enhanced photoluminescence fabricated by a facile method using polystyrene as template

Uniform hollow Sm3+-doped titania phosphors were prepared via a facile method using polystyrene spheres as template. After calcination at 500 A degrees C for 3 h, hollow TiO2:Sm3+ spheres with outer diameters of approximately 250 nm and a shell thicknesses ranging from 50 to 70 nm were obtained. A possible formation mechanism of the evolution process of the spheres was discussed in this paper. Photoluminescence (PL) results showed that the emission intensity of the as-prepared hollow TiO2:Sm3+ spheres was 2.1 times higher than that of amorphous nanoparticles (NPs). We propose that this PL enhancement is due to the unique hollow structures obtained.