Reactivity Enhancement of Nanoenergetic Materials Through Functionalized Al@Bi2O3/I2O5 Core-Shell Architecture

R. Singh, N. Badi, M. Hobosyan, K. Martirosyan
University of Houston, US

Keywords: nanoenergetic, core-shell, aluminum nanoparticles

Summary:

Most widely investigated nanoenergetic materials are Al/Fe2O3, Al/MoO3, Al/WO3 and Al/CuO and their reactivity properties, reaction rates and ignition energy are well documented. In this paper, we report our recent work on highly energetic core-shell type nanoenergetic materials using aluminum nanoparticles and oxides of bismuth and iodine. We have recently reported that Al/Bi2O3 and Al/I2O5 nanocomposites can release up to several times more gas production during explosion among traditional nanoenergetic materials. The incorporation of aluminum metal into the energetic formulations could increase the energy density through oxidation. The primary limitation factor for this energy is associated with incomplete combustion and excessive Al oxidation prior to combustion due to the formation of thick oxide layer. Therefore, thickness control and modification of the oxide layer at the surface of the nanoparticle is an utmost matter of importance. We have investigated coating approaches via different capping agents and surface functionalization to reduce or prevent the oxidation of these nanoscale particles. In this paper we present initial results on the effect of functionalization of outer layer of oxide as well as comparative reactivity of such core-shell based nanoenergetic materials by varying the coating thickness of the oxidizer. Sonochemical synthesis, aero sol-gel and mixed combustion methods and comparison of reactivity data will be discussed.