Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
10624446 | Ceramics International | 2016 | 27 Pages |
Abstract
Lead tellurite glass ceramics doped with variable amounts of Gd3+ ions and co-doped with fixed amounts of silver (Ag2O or Ag metallic nanoparticles, AgNPs) have been prepared and investigated by X-ray diffraction (XRD), density, electron paramagnetic resonance (EPR) and magnetic susceptibility measurements. The EPR spectra of the studied samples exhibit the typical ''U''-type shape with effective g-values of â6, 2.8, 2.0 and a weaker feature at gâ4.8. At higher contents of Gd3+ ions the spectral features are broadened and finally are dominated by a broad absorption line located at gâ2.0 and a weaker feature at gâ6. The broad EPR line centered at gâ2.0 is associated to the Gd3+ ions present predominantly as clustered species. The paramagnetic susceptibility (Ï) was measured at various temperatures and from the 1/Ï versus T dependence the molar Curie constant (CM) and the paramagnetic Curie temperature (θp) have been evaluated. Magnetic susceptibility data show that for low Gd2O3 contents, xâ¤3 mol%, the Gd3+ ions are randomly distributed in the host glass ceramics matrix and are present only as isolated species. For higher Gd2O3 contents, x>3 mol%, the Gd3+ ions appear as both isolated and antiferromagnetically coupled species.
Related Topics
Physical Sciences and Engineering
Materials Science
Ceramics and Composites
Authors
M. Bosca, L. Pop, L. Bolundut, N. Tothazan, G. Borodi, I. Vida-Simiti, R. Stefan, A. Popa, E. Culea, P. Pascuta,