Researchers at the US Army Aberdeen Proving Ground Research Laboratory were developing a high-strength aluminum alloy when they made an astonishing discovery. During routine testing of the alloy, water poured over its surface started bubbling and producing hydrogen gas, which is an unusual reaction: typically, aluminum exposed to water oxidizes, creating a protective barrier to prevent further reactions from occurring. However, in this case, the hydrogen-producing reaction just kept going.
Announced in July, the discovery has the potential to revitalize the hydrogen fuel industry. This would make hydrogen fuel cells much easier to use since there would be no need to pressurize and transport hydrogen gas for use. Instead, stable tanks of water and pieces of aluminum would be all needed. Previous attempts to drive the aluminum/water reaction required catalysts or high temperatures, and they were slow. Ultimately, they were only about 50 percent efficient, and obtaining the hydrogen took hours. In contrast, the method that uses this new alloy takes less than three minutes to achieve almost 100 percent efficiency.
The starting material for the alloy is inexpensive scrap aluminum, which is sufficient and cheap. This and other metals are used to create micron-scale grains, which are then arranged in a specific nanostructure.
Hydrogen gas has been hailed as a clean fuel for some time, but its widespread use has been hampered for practical reasons. It is bulky, demanding pressurization, making it tough to transport and store. This is where the new alloy stands apart.