Hydrogen storage for cars?

December 21, 2007

Hydrogen is the fuel of the future. Unfortunately, one problem remains: Hydrogen is a gas and cannot easily be pumped into a tank like gasoline. Storage in the form of solid hydrides, chemical compounds of hydrogen and a metal or semimetal, are good storage materials in principle, but have not been well suited to automotive applications. An American research team at the Ford Motor Company in Dearborn and the University of California, Los Angeles, has now developed a novel hydride that could be a useful starting point for the development of future automotive hydrogen-storage materials. As Jun Yang and his team report in the journal Angewandte Chemie, an "autocatalytic" reaction mechanism causes the composite made of three different hydrides to rapidly release hydrogen at lower temperatures and without dangerous by-products.

Certain hydrogen compounds, such as lithium borohydride (LiBH4 ) and magnesium hydride (MgH2), can release hydrogen and then take it up again. However, for automotive applications, they require temperatures that are too high to release hydrogen, the hydrogen release and uptake are far too slow, and decomposition reactions release undesirable by-products such as ammonia. In addition, these compounds can only be "recharged" under very high pressure and temperature conditions. The combination of two different hydrides (binary hydride) has previously been shown to improve things, as these compounds partly release hydrogen at lower temperatures than either of the individual components.

The researchers led by Yang went a step further and combined three hydrogen-containing compounds--lithium amide (LiNH2), lithium borohydride, and magnesium hydride--in a 2:1:1 ratio to form a ternary hydride. This trio has substantially better properties than previous binary materials.

The reason for this improvement is a complex sequence of reactions between the various components. The first reactions begin as soon as the starting components are ground together. Heating starts off more reactions, releasing the hydrogen. The mixture is "autocatalytic", which means that one of the reactions produces the product cores for the following reaction, which speeds up the entire reaction sequence. The result is a lower desorption temperature; the release of hydrogen begins at 150 °C. In addition the hydrogen is very pure because neither ammonia nor any other volatile decomposition products are formed. Recharging the ternary hydride with hydrogen can be accomplished under moderate conditions.
-end-
Author: Jun Yang, Ford Motor Company, Dearborn (USA), jyang27@ford.com
Title: A Self-Catalyzing Hydrogen Storage Material
Angewandte Chemie International Edition, doi: 10.1002/anie.200703756

Wiley

Related Hydrogen Articles from Brightsurf:

Solar hydrogen: let's consider the stability of photoelectrodes
As part of an international collaboration, a team at the HZB has examined the corrosion processes of high-quality BiVO4 photoelectrodes using different state-of-the-art characterisation methods.

Hydrogen vehicles might soon become the global norm
Roughly one billion cars and trucks zoom about the world's roadways.

Hydrogen economy with mass production of high-purity hydrogen from ammonia
The Korea Institute of Science and Technology (KIST) has made an announcement about the technology to extract high-purity hydrogen from ammonia and generate electric power in conjunction with a fuel cell developed by a team led by Young Suk Jo and Chang Won Yoon from the Center for Hydrogen and Fuel Cell Research.

Superconductivity: It's hydrogen's fault
Last summer, it was discovered that there are promising superconductors in a special class of materials, the so-called nickelates.

Hydrogen energy at the root of life
A team of international researchers in Germany, France and Japan is making progress on answering the question of the origin of life.

Hydrogen alarm for remote hydrogen leak detection
Tomsk Polytechnic University jointly with the University of Chemistry and Technology of Prague proposed new sensors based on widely available optical fiber to ensure accurate detection of hydrogen molecules in the air.

Preparing for the hydrogen economy
In a world first, University of Sydney researchers have found evidence of how hydrogen causes embrittlement of steels.

Hydrogen boride nanosheets: A promising material for hydrogen carrier
Researchers at Tokyo Institute of Technology, University of Tsukuba, and colleagues in Japan report a promising hydrogen carrier in the form of hydrogen boride nanosheets.

World's fastest hydrogen sensor could pave the way for clean hydrogen energy
Hydrogen is a clean and renewable energy carrier that can power vehicles, with water as the only emission.

Chemical hydrogen storage system
Hydrogen is a highly attractive, but also highly explosive energy carrier, which requires safe, lightweight and cheap storage as well as transportation systems.

Read More: Hydrogen News and Hydrogen Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.