Hydrogen is considered one of the potential fuel sources of the future. From using solar and wind energy to generate hydrogen as a power storage scheme, to hydrogen vehicles and backup power, the gas holds great promise for fuelling our world. However, three key challenges exists for the hydrogen economy -- production, storage and distribution.
New research from U.S. Department of Energy's Savannah River National Laboratory goes a long way to solving the problem of storage. In the new research, scientists take aluminum hydride (AlH3), also known as alane, and demonstrate a way that a standard pressure electrochemical process can be used to restore the material, which is damaged each time it releases hydrogen gas.
Typically hydrogen is stored as a liquid, but this method requires high pressures making it difficult to work with and potential dangerous. Solid storage is more promising, but for a material to be an ideal solid state storage candidate, it must meet a grueling set of criteria -- matching DOE gravimetric and/or volumetric performance targets (amounts stored); having sufficient thermodynamic character to release the gas when needed; and being able to reload the gas after release.
Only one material thus far has met these criteria -- alane. However, alane slowly degrades with each refill as the hydrogen carries away a bit of the metal. Chemical reformation techniques required high pressures and often are hindered by stable metal chloride formation. In the past electrochemical methods were tried by yielded no success. Now with the new method a cost-effective way of creating a self-healing alane storage system is at last possible.
Dr. Ragaiy Zidan of SRNL, lead researcher on the project says the research may also yield to breakthroughs in fields using related materials, such as thin film use and adduct based syntheses.
The research is reported in the journal Chem. Commun. and was paid for by a Department of Energy grant.