A novel process to produce air-stable core-shell nanoparticles for energetic applications

ABSTRACT: The use of energetic nanomaterials in munitions has the potential to increase lethality due to the high energy content provided by these materials. However, the propensity of nanoparticles, such as aluminum, to prematurely oxidize significantly reduces the total energy content. Such oxidation is unavoidable in any current large-scale commercial process for producing aluminum nanoparticles. In Phase I, we began developing a new class of core-shell nanoparticles with both a novel structure and a unique composition that addresses the drawbacks of state of the art metallic energetic nanoparticles. The core-shell composite nanoparticles are expected to have desirable functionalities, such as reduced oxygen contamination, intermetallic reaction for enhanced energy content, and air-stability. The feasibility of producing the core-shell nanoparticles, and their beneficial attributes, were demonstrated in Phase I. Building upon the Phase I proof of concept, and in collaboration with experts in the field of energetic materials, the proposed Phase II program provides a stepping stone towards developing a commercially viable process for producing nanocomposite energetic particles. The objectives of the Phase II program are (i) to scale up the technology and assemble a prototype production system, (ii) demonstrate a production rate of at least 500 g/batch in a 5 hour time period, and (iii) show superior combustion properties of the core-shell nanoparticles compared to state-of-the-art aluminum nanoparticles. We anticipate achieving a TRL of at least 5 by the end of the Phase II program. BENEFIT: Core-shell energetic nanoparticles can be used as solid propellants for commercial launch vehicles, satellites, military launch vehicles, and missiles. Additionally, these materials can be used to enhance military pyrotechnics to deliver improved battlefield illumination or compact and very high heat sources for the destruction of chemical and biological weapons. Further, they can be used to enhance the safety and performance of commercial pyrotechnics due to their high degree of stability in air and significantly faster rate of reaction. Other potential military applications include consumable port covers for ramjet engine inlets, ramjet fuels, self-ejecting combustible plumes for large-area heating, thermal battery heat sources and shaped-charge liners. Additional commercial applications include in situ soldering and welding, thermal battery heating pellets, airbags, drug injection, ammunition primers, detonators, electric matches, micro-actuators, micro-pumps, micro-thrusters, micro-switches and micro-valves.