$SrHfO_3$-based phosphors and scintillators

The heavily Ce-doped SrHfO 3 (SHO) and the undoped non-stoichiometric SHO sample sets were prepared by solid state reaction in powder form and their luminescence spectra and decay kinetics were measured. Concentration quenching effects and thermally induced ionization of the Ce 3+ excited states were followed and discussed in the former sample set. In the latter one new emission band at about 334 nm was found in Sr-deficient samples and temperature dependences of its emission intensity and decay times were studied in the detail. Room temperature decay time of about 180 ns and efficient and fast energy transfer from the host to the center of the 334 nm emission make this material promising candidate for X-ray phosphors.