In this paper, luminescent properties of Europium trivalent ion in the matrix with unbalanced charge of barium hafnate under UV radiation, with special emphasis on the D → F transition are reported. The synthesis was conducted by the hydrothermal route at 200 °C with a reaction time of 90 min using chlorides as raw materials. In order to determinate the luminescent quenching concentration, the samples were doped with different amounts of Europium trivalent ions being the sample doped with 1 and 3% at of Eu which shows the highest luminescent emission. X-ray diffraction analysis showed that the material crystallize in the cubic perovskite structure with space group Pm-3m. The Energy Dispersive Spectroscopy (EDS) shows there are not elements other those that Ba, Hf, O and Eu in the synthesized material. Photoluminescent emission spectra show peaks of emission associated with the D → F (J = 0,1,2,3,4) transitions, characteristics of europium ion. The D → F transition centered at 580 nm showed an unusual great intensity when it was excited with the wavelength associated with the charge transfer band (272 nm). Finally the decay time was measured in the D → F (J = 0,1,2,3,4) transitions using the sample doped with Eu (3% at).
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http://dx.doi.org/10.1016/j.apradiso.2019.108815 | DOI Listing |
Commun Chem
January 2025
Faculty of Engineering, Hokkaido University, Kita 13, Nishi 8, Kita-ku, Sapporo, Hokkaido, 060-8628, Japan.
Photoinduced metal-to-ligand (or ligand-to-metal) charge-transfer (CT) states in metal complexes have been extensively studied toward the development of luminescent materials. However, previous studies have mainly focused on CT transitions between d- and π-orbitals. Herein, we report the demonstration of CT emission from 4f- to π-orbitals using a trivalent europium (Eu(III)) complex, supported by both experimental and theoretical analyses.
View Article and Find Full Text PDFJ Colloid Interface Sci
January 2025
Departamento QUIPRE, Universidad de Cantabria, Avda. Los Castros 46 39005 Santander, Spain; Grupo de Nanomedicina, IDIVAL, Avda. Cardenal Herrera Oria s/n, 39011 Santander, Spain. Electronic address:
High-charge micas exhibit improved adsorption properties and are a promising alternative clay material for the engineered barrier in deep geological repositories. When combined with Eu cations, they serve as an in situ luminescent probe for tracking the physical-chemical changes occurring in this engineered barrier over the long term. Therefore, a better understanding of the local environment of the lanthanide is highly desirable to comprehend the specific behavior of these systems.
View Article and Find Full Text PDFJ Phys Chem B
January 2025
Sorbonne Université, CNRS, Physicochimie des Électrolytes et Nanosystèmes Interfaciaux, F-75005 Paris, France.
We developed a systematic polarizable force field for molten trivalent rare-earth chlorides, from lanthanum to europium, based on first-principle calculations. The proposed model was employed to investigate the local structure and physicochemical properties of pure molten salts and their mixtures with sodium chloride. We computed densities, heat capacities, surface tensions, viscosities, and diffusion coefficients and disclosed their evolution along the lanthanide series, filling the gaps for poorly studied elements, such as promethium and europium.
View Article and Find Full Text PDFJ Fluoresc
December 2024
School of Chemistry and Environmental Science, Xiangnan University, Chenzhou, Hunan, 423043, P. R. China.
In this work, trivalent europium (Eu) ion activated KSr(MoO) red phosphors have been synthesized through high-temperature solid-state reaction method at 750 ℃. Detailed analysis was conducted on the phase purity, morphology, and luminescence properties of the synthesized phosphors. X-ray diffraction (XRD) confirmed the successful formation of KSr(MoO):Eu phosphors with pure phase with space group С.
View Article and Find Full Text PDFChemosphere
November 2024
Department of Geological Sciences, BK21 School of Earth and Environmental Systems, Pusan National University, Busan, 46241, South Korea. Electronic address:
The sorption of Eu(III) by Na-substituted bentonite (Na-bentonite) was investigated as a function of pH and NaNO concentration ([NaNO]). At pH < ∼7.5, Eu(III) sorption decreased with the increasing [NaNO], whereas at pH > ∼7.
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