Atomic Layer Deposition of Oxidizer Coatings on Aluminum Nanoparticles to Fabricate Superthermite Explosives

"Energetic thermite composites are composed of a metal fuel (e.g. Al) and an oxidizer (e.g. Fe2O3). Thermite composites have a much higher reaction enthalpy per cm3 than conventional explosives such as TNT. However, current thermite composites do notyield a higher reactive power because of the large diffusion distance between the metal fuel and oxidizer in thermite powders. To minimize the diffusion distance, the oxidizer can be deposited directly on aluminum nanoparticles. This oxidizer-coated"all-in-one" superthermite explosive particle represents the ultimate in reactive power from a nanoscale energetic material. ALD NanoSolutions, Inc. proposes to deposit oxidizers on aluminum nanoparticles using atomic layer deposition (ALD) methods. TheALD surface chemistry and thin film growth will be investigated using Fourier transform infrared (FTIR) vibrational spectroscopy. The reaction conditions determined from the FTIR studies will then be utilized to coat large quantities of aluminumnanoparticles in a fluidized particle bed ALD reactor. The aluminum nanoparticles will be obtained from Technanogy in Irvine, California. The oxidizer-coated superthermite particles will be tested at Los Alamos National Laboratory. The results of thisPhase I work should demonstrate the development of superthermite particles as a superior explosive material. ALD NanoSolutions, Inc. owns options for exclusively utilizing and licensing the intellectual property developed over the last five years byco-founders Profs. George and Weimer at the University of Colorado. The company was founded to develop commercial markets for this ALD technology. One of the largest potential markets under consideration is the coating of fine powders with ultrathin andconformal films. Depositing oxidizers directly on aluminum nanoparticles to fabricate superthermite explosive particles is an excellent ALD application. These "all-in-one" superthermite particles are anticipated to display much higher reactive powersthan conventional explosives. Tests of nanoscale powders