Jiménez JA, Rutland H. Pd
2+-induced quenching of the UV emission from Gd
3+ ions in phosphate glass.
SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2021;
249:119357. [PMID:
33383462 DOI:
10.1016/j.saa.2020.119357]
[Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/12/2020] [Revised: 12/09/2020] [Accepted: 12/16/2020] [Indexed: 06/12/2023]
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.
Collapse