Luminescence properties of cerium doped nanocrystalline yttrium silicate

Here we report the preparation of nanocrystalline silica capped yttrium silicate doped with cerium and a study on its photoluminescence (PL) properties. The preparation method presented is simple and unique and can easily be scaled up for bulk production. The material shows blue luminescence at room temperature, and it is enhanced by a few orders of magnitude upon annealing. The PL intensities of these nanocrystalline samples are much stronger than similar bulk samples. The annealing temperatures required are much less than the bulk sample formation temperatures. Such annealing related PL enhancement is attributed to the formation of the optimum nanocrystalline size required for strong luminescence from nanoparticles due to the doped rare earth ions and quantum confinement related effects. It was also suggested that nano-Y 2 SiO 5 has a relatively more intense blue emission than the nano-Y 2 Si 2 O 7 phase. This is attributed to the position of the 5d level of Ce 3 + in the energy band.