2002-09

Preparation and general physical properties of polycrystalline PrBa2Cu3O7-y obtained from sol-gel precursors

Polycrystalline samples of PrBa2Cu3O7– y were prepared through two different routes: (a) mixing Pr6O11, BaCO3, and CuO; (b) sol-gel precursors. The samples were heat-treated in the temperature range 700 <= T <= 930 ºC and under different atmospheres, (Argon and air). Oxidation of these compounds, based on the results of thermogravimetric analysis, TGA, was performed at low temperatures, from 300 to 400 ºC, for time intervals as long as 120 h. The crystal structure was determined by measurements of X-ray powder diffraction and revealed that samples heat-treated at 810 ºC in Ar and for 130 ...

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