Author : K. Kalyan Chakravarthi and M. Rami Reddy

The synthesized glasses of CaO-PbO-B2O3-SiO2: Pr2O3 – V2O5 were prepared by conventional melt-quenching process. The optical absorption spectra exhibit different transition from various energy levels presence of simple Pr3+ ions and V4+ ion identities in the UV-vis-NIR region. The EPR spectra exhibited high intense hyperfine splitting of equidistant two sets of eight lines due to presence of VO2+ paramagnetic ion. The g-factor shows a centred at g≈ 1.9857. The PL spectra shows seven emission transitions observed intra-configurational f2-f2 of Pr3+ ions. The luminescence spectra of V4+ ion contain glass exhibited emission transition of 2E2g → 2T2g of octahedral geometry. The V4+ – Pr3+ ions co-doped glass samples exhibited several emission transitions. Among all the emission transitions, 3P0→ 3H6 (625 nm) are identified to be prominent emission transitions. With gradual increase of V4+ ion concentration, the 3P0→ 3H6 emission transition intensity to be increased may folds with respect to that of V4+ ions free glass. The efficient energy transfer from octahedral V4+ → Pr3+ ions (3d1 → 4f2). Finally, it is concluded that the preferable PrV1.0 glass for getting highest efficient luminescence of Pr3+ ions due to energy transfer of metal to metal intervalence charge transfer state (d1 → f2).

Keywords: Borosilicate glasses, Optical Absorption, XRD, FTIR, EPR, PL and Energy transfer from d1 → f2 ions.