Partager

Supraconductivité, visualisation de la structure, promotion de la résistance mécanique et spectre Raman du 123-YBCO dopé au hafnium, synthétisé grâce à une voie employant l'urée comme précurseur.

Superconductivity, structure visualization, mechanical strength promotion and Raman spectra of hafnium-doped-123-YBCO synthesized via urea precursor route.

Auteurs : ELSABAWY K. M.

Type d'article : Article

Résumé

The pure YBCO (YBa2Cu3O7) and its variant hafnium containing superconductors with general formula: Y(1-x)Hf(x)Ba(2)Cu(3)O(z), where x = 0.1, 0.2, and 0.4 mole, respectively, were synthesized by solution route using urea as precursor forming agent. X-ray measurements indicated that Hf(4+) ions have a negligible effect on the main crystalline structure and substitute Y-sites successfully in lattice structure of 123-YBCO at low levels of hafnium doping (x = 0.1 ? 0.2 mole). From SE-microscopy mapping and EDX elemental analysis Hf(4+) was detected qualitatively with good approximation to the actual molar ratio but not observed at 123-YBCO grain boundaries which confirm that hafnium (IV) has diffused regularly into material bulk of superconducting 123-YBCO-phase at low levels of concentrations. Structure visualization of Hf-doped-123-YBCO was made to confirm success of hafnium substitutions inside crystal lattice on Y-sites of 123-YBCO superconductors. Hafnium dopings affected sharply on the main vibrating modes of YBCO regime particularly on the apical oxygen (O4) vibrational mode A(1)g. Magnetic susceptibility measurements proved that hafnium dopings have strong effect on the transport properties of YBCO-composites regime. Hafnium promotes mechanical tensile coefficient recording maxima 35.7 MPa for x = 0.4 mole. [Reprinted with permission from Elsevier. Copyright, 2011].

Détails

  • Titre original : Superconductivity, structure visualization, mechanical strength promotion and Raman spectra of hafnium-doped-123-YBCO synthesized via urea precursor route.
  • Identifiant de la fiche : 30003274
  • Langues : Anglais
  • Source : Cryogenics - vol. 51 - n. 8
  • Date d'édition : 08/2011
  • DOI : http://dx.doi.org/10.1016/j.cryogenics.2011.05.004

Liens


Voir d'autres articles du même numéro (4)
Voir la source

Indexation