title: Hydrogen-on-demand using metallic alloy nanoparticles in water.
abstract: Hydrogen production from water using Al particles could provide a renewable energy cycle. However, its practical application is hampered by the low reaction rate and poor yield. Here, large quantum molecular dynamics simulations involving up to 16,611 atoms show that orders-of-magnitude faster reactions with higher yields can be achieved by alloying Al particles with Li. A key nanostructural design is identified as the abundance of neighboring Lewis acid-base pairs, where water-dissociation and hydrogen-production require very small activation energies. These reactions are facilitated by charge pathways across Al atoms that collectively act as a "superanion" and a surprising autocatalytic behavior of bridging Li-O-Al products. Furthermore, dissolution of Li atoms into water produces a corrosive basic solution that inhibits the formation of a reaction-stopping oxide layer on the particle surface, thereby increasing the yield. These atomistic mechanisms not only explain recent experimental findings but also predict the scalability of this hydrogen-on-demand technology at industrial scales.
authors: Collaboratory for Advanced Computing and Simulations, ‡Department of Physics and Astronomy, §Department of Computer Science, and ∥Department of Chemical Engineering and Materials Science, University of Southern California , Los Angeles, California 90089-0242, United States.
authors: Kohei
authors: K
authors: Shimamura
authors: Fuyuki
authors: F
authors: Shimojo
authors: Rajiv K
authors: RK
authors: Kalia
authors: Aiichiro
authors: A
authors: Nakano
authors: Ken-Ichi
authors: K
authors: Nomura
authors: Priya
authors: P
authors: Vashishta