RESUMO
In this paper, luminescent properties of Europium trivalent ion in the matrix with unbalanced charge of barium hafnate under UV radiation, with special emphasis on the 5D0 â 7F0 transition are reported. The synthesis was conducted by the hydrothermal route at 200⯰C with a reaction time of 90â¯min using chlorides as raw materials. In order to determinate the luminescent quenching concentration, the samples were doped with different amounts of Europium trivalent ions being the sample doped with 1 and 3% at of Eu3+ which shows the highest luminescent emission. X-ray diffraction analysis showed that the material crystallize in the cubic perovskite structure with space group Pm-3m. The Energy Dispersive Spectroscopy (EDS) shows there are not elements other those that Ba, Hf, O and Eu in the synthesized material. Photoluminescent emission spectra show peaks of emission associated with the 5D0 â 7FJ (Jâ¯=â¯0,1,2,3,4) transitions, characteristics of europium ion. The 5D0 â 7F0 transition centered at 580â¯nm showed an unusual great intensity when it was excited with the wavelength associated with the charge transfer band (272â¯nm). Finally the decay time was measured in the 5D0 â 7FJ (Jâ¯=â¯0,1,2,3,4) transitions using the sample doped with Eu3+ (3% at).