부산대학교 도서관

This article establishes the correlations among structural, electronic, optical and magnetic properties of rare-earth Pr ion-doped nanocrystalline maghemite samples. All the samples with a generic formula γ-Fe2-xPrxO3 (x = 0.00, 0.02, 0.04 and 0.06) were fabricated using the conventional co-precipitation method. Powder x-ray diffraction profile verified the crystallographic phase-purity together with the presence of cubic spinel structure of all the samples. Mean sizes of as-synthesized samples containing tiny crystallites were ranged from 10 to 21 nm. Compressive strain existed inside the nanocrystals as confirmed by Williamson–Hall plots. An indirect optical band gap within the range of 1.27 eV–1.95 eV was obtained using Tauc plots. Frequency-dependent conductivity measurement revealed that the hopping of electrons was the primary charge transfer process for all the samples. Because of the completely paramagnetic character of Pr3+ ions near room temperature, all the magnetic parameters like saturation magnetization, coercivity, magnetic moment and anisotropy constant were noted to decrease linearly for higher Pr content nanosized maghemite samples as verified by the room temperature hysteresis curves. [ABSTRACT FROM AUTHOR]