Showing 2 results for Farbod
H. Shalchian, A. Farbod, H. Beygi, S. A. Sajjadi,
Volume 12, Issue 1 (march 2015 2015)
Abstract
High energetic aluminum nanoparticles are mainly used as additive in solid rocket propellants. However,
fabrication of these aluminized energetic materials is associated with decreasing the burning rate of propellants due
to problems such as oxidation and agglomeration of nanoparticles. In this study, to improve combustion performance
of aluminum nanoparticles, coating by metallic Ni shell was studied. Nickel coating of aluminum nanoparticles was
performed through electroless deposition (ED) subsequently, morphology and chemical composition of Ni-coated
nanoparticles were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM),
energy dispersive spectroscopy (EDS) and X-ray diffraction (XRD). These studies show that a uniform Ni layer with a
thickness of 10nm is coated on the surface of Al nanoparticles. Thermal analysis of uncoated and Ni-coated aluminum
nanoparticles was done using differential thermal analysis (DTA) and thermo gravimetric analysis (TGA). The results
of thermal analysis indicate that, coating the aluminum particles by Ni, leads to improvement in combustion
performance of aluminum nanoparticles through decreasing critical ignition temperature, ignition delay time of the
nanoparticles and promoting the ignition by exothermic chemical reactions between Al and Ni
Sara Tafaroji, Mansoor Farbod,
Volume 21, Issue 0 (IN PRESS 2024)
Abstract
The structural and electrochemical properties of Gd-doped perovskite oxides were investigated to improve the performance of solid oxide fuel cell (SOFC) cathodes. Ba0.5Sr0.5-xGdxCoO3-δ and BaSr1-xGdxCo2O5+δ (BSGC) compounds were synthesized via a sol–gel thermolysis method to elucidate the effects of Gd incorporation on crystal structure, microstructure, and electrochemical activity. X-ray diffraction (XRD) and scanning electron microscopy (SEM) confirmed the coexistence of simple and double perovskite phases, with Gd substitution leading to finer grains (down to 0.4 ± 0.14 μm) and improved phase homogeneity. Area-specific resistance (ASR) and conductivity measurements revealed a strong structure–performance relationship. The optimal composition, Ba0.5Sr0.3Gd0.2CoO3-δ, exhibited an exceptionally low ASR of 0.12 Ω cm² at 700 °C which further decreased to a minimum of 0.04 Ω cm² at 850 °C, significantly outperforming GdBaCo2O5+δ (GBCO), (1.76 Ω cm²). These findings demonstrate that rational structural design through rare-earth doping effectively enhances oxygen transport and electrochemical activity, providing a promising pathway for high-performance intermediate-temperature SOFC cathodes.
