(528b) Preparation of the Core-Shell Aluminum Nanoparticle with a Magnetic Nickel Shell

Aluminum nanoparticle has many advantages as the metal fuel in solid propellants for rockets, such as fast burning rate, high burning efficiency and no agglomeration in the combustion process. Because aluminum nanoparticles are very oxidative to form alumina, it is necessary to coat their surface with inert materials to prepare the core-shell aluminum nanoparticles. In this work, we proposed a novel process to prepare nanoparticles with an aluminum core and a magnetic shell. The preparation process consists of three steps as the purification of aluminum nanoparticles by differential centrifugation, the corrosion reaction of alumina layer, and the in situ displacement reaction of nickel ion with aluminum to form a magnetic nickel shell. The magnetic shell makes the nanoparticles can be easily separated from the liquid phase by the magnetic force. The nickel shell tightly bonds with the aluminum core, and protects it from the oxidation. The monodisperse nanoparticles with uniform shells can be produced using this new process. The methodology for regulating the size, structure and performance of the nanoparticle was investigated as well as the mechanism involved.