ISSN:
1662-0356
Source:
Scientific.Net: Materials Science & Technology / Trans Tech Publications Archiv 1984-2008
Topics:
Natural Sciences in General
,
Technology
Notes:
In this work we present the results about the preparation of the superconductorYBa2Cu3O7-δ (Y123) by sol-gel method using oxalate precursors. Samples were prepared bydissolving stoichiometric mixtures of Y(OOCCH3).4H2O, Ba(OOCCH3)2 and Cu(OOCCH3)2.H2Oacetates in aqueous solution of oxalic acid, HCOO-COOH. The particulate sols obtained (2g.) weredivided in two parts (1g. each one), from which the first one (sample A) was grinded, pellet,calcined (860ºC) and sinterised at 860ºC in oxidizing atmosphere, the second part (sample B) wasgrinded, pellet, calcined at 880ºC and finally sinterized at 880ºC in the same conditions, the XRDrevels the superconductor Y123 is formed in the first sample, but coexisting with remarkablepresence of the secondary phases: CuO, BaCu3O4, BaCO3 and BaCuO2, while in sample B the XRDreveals the obtention of high purity monophase Y123, the ac susceptibility measurement using aQuantum Design (SQUID) magnetometer indicates TC(onset)=92K for this sample, moreover theRietveld refinement was done taking the orthorhombic Pmmm Y123 spatial group as a model, thissuggest the cell´s parameters a=3.839Å, b=3.899 Å and c=11.702Å as reported in the literature.Therefore for the preparation of Y123-superconductor using oxalate precursors, the optimussintering temperature is 880ºC
Type of Medium:
Electronic Resource
URL:
http://www.tib-hannover.de/fulltexts/2011/0528/01/42/transtech_doi~10.4028%252Fwww.scientific.net%252FAST.47.37.pdf
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