Cu-Cr-O nanocomposites: Synthesis and characterization as catalysts for solid state propellants

In this article we present the synthesis of Cu-Cr-O nanocomposites via a citric acid (CA) complexing approach and the evaluation of the assynthesized Cu-Cr-O nanocomposites as additives for the catalytic combustion of AP (ammnonium perchlorate)-based solid state propellants. Techniques of thermo-gravimetric/differential thermal analyzer (TG-DTA), X-ray diffraction (XRD), transmission electron microscopy (TEM) as well as scanning electron microscopy (SEM) have been employed to characterize the thermal decomposition procedure, crystal phase, microstructural morphologies and grain size of the as-synthesized materials, respectively. The results show that well-crystallized Cu-Cr-O nanocomposites can be produced by using a temperature as low as 600 degrees C. Phase structure of the as-obtained Cu-Cr-O nanocomposites depends on the Cu./Cr molar ratio in the starting reactants. Addition of the as-synthesized Cu-Cr-O nanocomposites as catalysts enhances the burning rate as well as lowers the pressure exponent of the AP-based solid state propellants considerably. Noticeably, solid state propellants containing Cu-Cr-O nanocomposites, with a Cu/Cr molar ratio of 0.7 exhibits the most stable combustion at all pressures. (C) 2007 Elsevier Masson SAS. All rights reserved.