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The facile synthesis of nanocrystalline CuFe2O4 materials were obtained by solid state salt flux technique using the reaction mixture with different ratio (1:1, 1:2, 1:3, 0:4 and 4:0) of NaCl:KCl flux at 950-1000°C. Though all the flux synthesized materials show good quality tetragonal phase CuFe2O4 materials, no significant variation in lattice parameters are seen due to variation in flux concentration. The extracted average crystalline sizes are in the range of 25.5 - 30.61 nm for different nanocrystalline CuFe2O4 materials. The HRSEM micro-images of flux synthesized nanocrystalline CuFe2O4 materials indicate that the grains have different shapes in the range of ~374 nm to ~782 nm due to polycrystalline nature. [ABSTRACT FROM AUTHOR]

The nanocrystalline RuSr2Eu1.5Ce0.5Cu2O10-δ (referred to as Ru1222Eu) materials were successfully prepared by mechano-thermal route and studied the Ru1222Eu materials by powder XRD, FT-IR, SEM-EDX and acsusceptibility measurements. The as-milled powder annealed at 950 - 1000°C is crystallized in nearly single tetragonal phase of Ru1222Eu materials with average crystalline size of ~40 nm. Agglomeration of fine particles is seen through SEM micro-images in the Ru1222Eu phase materials. Contrary to magneto-superconductivity, a magnetic ordering is seen at ~60 K for Ru1222Eu phase under low applied field of 0.5 Oe at 10 Hz. [ABSTRACT FROM AUTHOR]

In this report, the nanocrystalline BaFe12O19 materials obtained by modified co-precipitation method using Na2CO3 and NaOH as precipitating agent are presented. In the modified co-precipitation process, instead of washing the co-precipitated product in mother liquor with de-ionized water, it was dried in a heating mantle, which has major influence as self flux in the single phase formation of BaFe12O19 phase. The co-precipitated product was annealed at 1000°C for 2 h under ambient pressure to obtain the required BaFe12O19 phase. The results based on XRD, average crystalline size, FT-IR, HR-SEM and EDX are reported. The annealed BaFe12O19 materials showed nanocrystalline single hexagonal phase with average crystalline size of ~102 nm. The annealed BaFe12O19 materials show particle sizes in the range of 280 ~326 nm and the thickness of ~57 nm in the high resolution micro-images. [ABSTRACT FROM AUTHOR]

We have prepared nanocrystalline NbSr2Pr1.5Ce0.5Cu2O10-δ (Nb1222Pr) material by annealing the ball milled powder at 1000°C for 24h and studied by various characterization techniques such as TG-DTA, XRD, FT-IR, NIR, SEM-EDX, magnetization and electrical resistivity. Significant difference is seen in the TG-DTA curves of the as-milled powder due to ball milling. The annealed Nb1222Pr material is crystallized in tetragonal symmetry with lattice parameters, a = 0.3887(3) nm and c = 2.878(2) nm with reduced average particle size of ~42.67 nm. Agglomeration of fine spherical particle sizes in the range of ~180 - 280 nm is seen through SEM micro-image. The variation in the crystalline sizes of the Nb1222Pr phase obtained from XRD and SEM image indicate the polycrystalline characteristic of fine nanocrystalline particles. Neither superconductivity nor magnetic ordering is seen for the Nb1222Pr phase down to 5 K under 100 Oe. The four probe resistivity measurement reveals the semiconducting behavior of the Nb1222Pr phase. [ABSTRACT FROM AUTHOR]

In this brief article, the synthesis of nanocrystalline CoFe2O4 material by molten salt flux (NaCl:KCl) method and their characterization by XRD, FTIR, and HRSEM-EDX are reported. The molten salt flux synthesized material reveals single cubic CoFe2O4 phase with lattice parameter, a = 0.8384(6) nm and average crystalline size, D of 44.66 nm. The fine particles with the size of 147 ~ 386 nm is seen through HRSEM images on the surface of nanocrystalline CoFe2O4 materials. [ABSTRACT FROM AUTHOR]