I. Kazeminezhad, N. Monzavizadeh, M. Farbod,
Volume 29, Issue 2 (Dec 2010)
Abstract
In this work, NiCu and CoCu alloy nanowires were prepared by electrodeposition within nuclear track-etched polycarbonate membranes with the nominal diameter of 30nm. Electrodeposition was carried out under potentiostatic control with three electrodes. In order to grow CoCu nanowires and NiCu nanowires, an electrolyte containing salts of Co and Cu, and an electrolyte containing the salts of Ni and Cu were used respectively. Then, the potentiodynamic behavior of each electrolyte was investigated by its CV curves, and the optimum potentials for the deposition of Ni, Co and Cu were selected according to these curves. A TEM microscope was used to study the structure of the nanowires. The results showed that the crystalline growth is polycrystalline and the diameter of the wires is about 80 nm. Apart from that, some nanowires were deposited under different deposition voltages. EDX analysis showed that the atomic weight of Ni and Co in all samples vanishes in the potentials between -0.5V to -0.8V which indicates that pure Cu atoms are deposited at these voltages. Deposition of Ni and Co starts at more negative voltages such as -0.9 and -0.85 V, respectively.
S. E. Mousavi Ghahfarokhi, F. Bazdar, I. Kazeminezhad,
Volume 36, Issue 2 (Journal of Advanced Materials-Summer 2017)
Abstract
In this paper, Ni-doped lead hexaferrites (PbFe12-xNixO19) nanoparticles with x = 0.2 were prepared by sol- gel method. Then, the effect of annealing temperature on its structural, magnetic and dielectric properties was studied. First, the dryed gel was evaluated by Thermogravimetry-Differential Thermal Analysis (TG/DTA) and then, the structural morphology, magnetic and dielectric properties of samples have been characterized by Fourier Transform Infrared (FT-IR) spectroscopy, X-Ray Diffraction (XRD), Scanning Electron Microscopy (SEM), Vibrating Sample Magnetometer (VSM) and LCR meter. The results of x-ray diffraction patterns show that by increasing annealing temperature up to 800 °C, PbFe11.8Ni0.2O19 phase percentage in the samples increases. Also, by increasing annealing temperature, the magnetization increases because the unwanted phases disappear and pure and single-phase lead hexaferrite are formed. By increasing frequency, first the AC electrical conductivity of the samples decreases and then increases. These variations have been explained by Maxwell- Wanger model. The result measurements show that the best sample is PbFe11.8Ni0.2O19 with annealing temperature of 800 °C for 3 h.
