Abstract
This paper reports on the influence of Pd2+ ions on the ultraviolet emission from Gd3+, investigated in barium phosphate glass as model matrix. The glasses were prepared by the melting technique and characterized by X-ray diffraction (XRD), Fourier transform-infrared (FT-IR) spectroscopy, optical absorption, and photoluminescence (PL) spectroscopy including decay kinetics assessment. The XRD data confirmed the amorphous nature of the glasses, whereas FT-IR spectra indicated the basic structural features of PO4 tetrahedra. The optical absorption analysis showed that addition of PdO up to 0.3 mol% lead to significant growth of the visible Pd2+ d-d absorption band around 415 nm, with ultimately some decrease in the optical band gap energies assessed through Tauc plots. Further, significant PL quenching of Gd3+ ions emission around 312 nm was observed with increasing PdO contents, alongside increased decay rates for the 6P7/2 emitting state in Gd3+. An analysis of quenching constants was ultimately performed comparing results from emission intensity with the decay rates. It is suggested that a Gd3+ → Pd2+ excitation transfer and/or absorption competition lead the quenching process with a contribution from a channel depopulating the 6P7/2 metastable state.
Original language | English |
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Article number | 119357 |
Journal | Spectrochimica Acta - Part A: Molecular and Biomolecular Spectroscopy |
Volume | 249 |
DOIs | |
State | Published - Mar 15 2021 |
Keywords
- Energy transfer
- Glasses
- Luminescence
- Optical properties
- Rare earths