Nanopowders of HoBa2Cu3O7-ä have been prepared by a citrate gel modification of the sol–gel technique atdifferent calcination temperatures, using high-purity nitrate salts of Y, Ba and Cu as starting materials and citric acid as complex agent. According to x-ray powder diffraction analysis and SEM images the nanoparticles have orthorhombic structure. Room temperature magnetizations measured using a vibrating sample magnetometer (VSM) showed that Nanoparticles of superconducting HoBa2Cu3O7-ä exhibit ferromagnetism at room temperature while the bulk-like sample, obtained by heating the Precursor at high temperature, shows a linear magnetization curve

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