Synthesis of spherical luminescent particulate coatings

In this communication, we show the feasibility of the pulsed laser ablation technique to make very thin, uniform luminescent coatings on particulate systems. To deposit continuous particulate coatings, the laser-induced plume from the target comes in contact with an agitated bed of core particles (size 1 μm). The pressure and nature of the background gas (inert or active) controls the cluster size of the particles in the laser plume. Experiments were conducted for laser deposition of phosphor nanoparticles on SiO2 core particles by pulsed excimer laser (wavelength=248 nm and pulse duration=25 ns) irradiation of a yttria:Eu (Y2O3:Eu3+) sputtering target.