We use aluminum to make planes lightweight, store sodas in recyclable containers, keep the walls of our homes energy efficient and ensure that the Thanksgiving turkey is cooked to perfection. Now, thanks to a group of Japanese researchers, there may soon be a new application for the versatile metal: hydrogen storage for fuel cells.
Lightweight interstitial hydrides -- compounds in which hydrogen atoms occupy the interstices (spaces) between metal atoms -- have been proposed as a safe and efficient means for storing hydrogen for fuel cell vehicles. Hydrides using magnesium, sodium and boron have been manufactured, but so far, none have proven practical as a hydrogen repository. An aluminum-based alloy hydride offers a more viable candidate because it has the desired traits of light weight, no toxicity to plants and animals, and absence of volatile gas products except for hydrogen. Until now, however, only complex aluminum hydrides -- unsuitable for use as a hydrogen storage system -- have been created.