Structural and photoluminescence studies of cerium europium co-doped Strontium barium niobate

摘要

Cerium Europium co-doped Strontium barium niobate (SBN) nano ceramic systems at different concentrations were prepared by sol gel method. The structural properties were characterised by X-ray diffraction, FTIR and Raman spectroscopy. X-ray diffraction analysis confirms the tetragonal structure of the prepared system. EDAX analysis confirms the components present in the sample. SEM image shows the needle like morphology of the nano system. XRD image confirms the particle size and crystalline planes of the prepared nanosized cerium europium doped SBN with the standard value. The broad absorption peak at 291 and 273 nm were observed for 0.1, 0.2 % Cerium, Europium co-doped SBN nano system. The absorption in the samples is from direct transition and the values of energy gap were calculated as 2.11 eV and. 2.27 eV. Photoluminescence studies shows the broad emission peaks at 419, 447, 493 nm due to 5d-4f Ce~(3+) transition levels. The peaks at 440, 449 nm were also observed due to the emission from SBN and less intense peaks at 558, 576, 588 nm due to the ~5D_0-~7F_0, ~7F_1 transitions of Eu~(3+) when excited at 305 nm wavelength. From the measured luminescence decay profiles, the tri-exponential lifetime of the 0.1% Cerium, Europium co-doped SBN nano system was calculated at 440 nm emission wavelength. Therefore the cerium europium co-doped SBN can be used for optical applications.