Synthesis, structural and electrical characterizations of DySr.sub.5./sub.Ni.sub.2.4./sub.Cu.sub.0.6./sub.O.sub.12-δ./sub..

0369776 - FZÚ 2012 RIV US eng J - Journal Article
Hamdi, S. - Ouni, S. - Chaker, H. - Rohlíček, Jan - Ben Hassen, R.
Synthesis, structural and electrical characterizations of DySr₅Ni_2.4Cu_0.6O_12-δ.
Journal of Solid State Chemistry. Roč. 184, č. 11 (2011), s. 2897-2901. ISSN 0022-4596. E-ISSN 1095-726X
Institutional research plan: CEZ:AV0Z10100521
Keywords : Rietveld refinement * K₂NiF₄-type structure * electrical resistivity * oxygen vacancies * iodometric titration
Subject RIV: BM - Solid Matter Physics ; Magnetism
Impact factor: 2.159, year: 2011

A new compound DySr5Ni2.4Cu0.6O12-δ has been prepared by sol gel method and annealed at 1473 K in 1 atm of Ar gas flow. The X-ray diffraction (XRD) is used for phase identification. The sample shows to adopt the K2NiF4-type structure based on tolerance factor calculation. XRD analysis using the Rietveld method was carried out and it was found that DySr5Ni2.4Cu0.6O12-δ (Dy0.33Sr1.67Ni0.8Cu0.2O4-δ) compound crystallizes in tetragonal symmetry with space group I4/mmm (Z = 2). The lattice parameters are found to be at room temperature a = 3.7696(5) ˚A and c = 12.3747(2) A . The final relia! bility indices were: RB = 5.219% and χ2 = 3.47. Four probe electrical resistivity measurements were performed versus temperature in the range 294-579 K. A semiconducting behaviour over the whole range of temperature, with a conductivity maximum of 0.4 S cm-1 is observed at 510 K.
Permanent Link: http://hdl.handle.net/11104/0006757