Field deployable energy is typically heavy and/or volatile, limiting its use in far-forward or backcountry situations. Military convoys must also contend with increased vulnerability created by transporting these fuels, whether they be liquid petroleum fuels or compressed liquid hydrogen.
In search of alternatives, the Air Force Research Laboratory developed an aluminum (Al)-based stable energy carrier that reacts with any liquid containing water to yield a rapid and thorough generation of hydrogen (H2). Aluminum is normally nonreactive due to its thin oxide surface layer. This aluminum–water reaction is made possible by creating aluminum oleic acid core-shell nanoparticles via sonochemistry. The resulting reaction, which requires a pressure tank to contain, is nearly complete (>95%), offers a tunable conversion rate, a high yield (1/2 liter H2 gas from 1g Al), and an environmentally benign byproduct.
The technology has been demonstrated as a source of hydrogen gas for a range of applications, from power generators, such as fuel cells, to fuel for race car engines. Because the reaction is spontaneous and exothermic, packaging is required to isolate the Al nanomaterial from water until a reaction is desired. First responders and special operators having diverse and field forward power needs may be early adopters.
- Aluminum itself is stable, abundant, and carries a high energy potential
- Al nanoparticles are manufactured efficiently with sonochemistry
- Al nanoparticles in the presence of water convert thoroughly to H2 (>95%) at tunable rates, yielding ½ liter of H2 gas per 1g of feedstock, and generating an environmentally benign byproduct
- H2 gas from Al nanoparticles can be used in a range of applications from fuel to lift to energetics
- US patent 9,011,572 is available for license
- This technology has been scaled up in the lab and tested in real world applications. Small gram quantity samples may be available under a material transfer agreement to qualified applicants.
- More information in Journal of Materials Chemistry, 2011 21,12173