Luminescence of Eu3+/Eu2+ In PVA Film: Transitions from the 5D0 Level and its Lifetime Measurement

We have synthesized Eu3+ doped poly vinyl alcohol (PVA) polymer film by the solution-casting method. The vibration features of the film are analyzed by using the FTIR spectrum. In the FTIR spectrum, many peaks are observed and correlate with different branches of vibrations. On excitation of 325 nm, Eu3+ ions emit at 579 nm, 592 nm, 615 nm, 649 nm, 698 nm through transitions 5D0→7F0, 5D0→7F1, 5D0→7F2, 5D0→7F3, 5D0→7F4 respectively. These peaks are verified with the help of Eu3+ energy level diagram. In addition, we observed a broad peak of Eu2+ in the range 450 nm to 550 nm centered at 500 nm. Some stark splitting also has been observed in transitions 5D0 →7F0 and 5D0→7F4. The micron - second lifetime of the 5D0 level of Eu3+ is observed and correlated with the emission spectrum.