Synthesis and Optical Characterization of Pr~(3+) Doped UV Emitting Luminescent Ceramics

摘要

UV emitting luminescent materials are of strong interest for UV emitting fluorescent lamps driven by a Hg low-pressure or a by Xe excimer discharge. Pr~(3+) doped host lattices exhibit efficient UV emission upon deep UV excitation, if the site of the host lattice, where Pr~(3+) is located, is suitable for this purpose. This work deals with Pr~(3+) activated VUV ceramic luminophores, i.e. materials, which show efficient luminescence upon 160 nm excitation. As host lattices for the potentially UV emitting Pr~(3+) ion aluminates and silicates have been studied. All samples were prepared by conventional mix and fire synthesis techniques with metal oxides as starting materials. Firstly, powder samples were annealed between 1000 and 1700°C and secondly, ceramic samples were repeatedly thermally treated at similar temperatures after pressing. It is demonstrated that translucent ceramics show mainly UV luminescence upon deep UV excitation, while excitation by a blue 450 nm LED results in green to red luminescence with a similar decay time as observed for single crystals.