New Composite Material Designed for Storing Hydrogen

Hydrogen-fueled vehicles have been in the making for decades, but one thing that prevented them from being widely adopted was the lack of a storage material efficient enough to contain large amounts of the fuel. Now, the issue may have been solved in the United States.

Researchers with the US Department of Energy (DOE) Lawrence Berkeley National Laboratory (Berkeley Lab) create a new high-capacity, hydrogen-storing type of composite material, that they say can be filled with large amounts of the important chemical.

The main advantage that hydrogen has is that it does not release pollutants, greenhouse gases, or other dangerous substances while propelling a vehicle. Its only waste product is water, chemists explain.

Unlike gasoline or diesel, the stuff is readily available, as it can be extracted from the world's oceans. It also has a higher energy density than all fossil fuels. However, the material does have a disadvantage.

Experts have until now been unable to create an advanced storage system for the stuff. Such a construct would need to operate within very specific parameters. The chemical needs to be stored safely and densely, but at the same time it needs to be readily available for use.

The composite material the Berkeley Lab team developed for hydrogen storage meets these criteria. IT is made of magnesium metal nanoparticles, mingled inside a matrix constructed of the Plexiglas-related polymer called polymethyl methacrylate.

The nanocomposite material is pliable, and capable of absorbing and releasing massive amounts of hydrogen at only modest temperatures. But the most remarkable thing about it is that it does not oxidize the metal after such a cycle is complete. This is a major breakthrough.

“This work showcases our ability to design composite nanoscale materials that overcome fundamental thermodynamic and kinetic barriers to realize a materials combination that has been very elusive historically,” explains investigator Jeff Urban.

“Moreover, we are able to productively leverage the unique properties of both the polymer and nanoparticle in this new composite material, which may have broad applicability to related problems in other areas of energy research,” the scientist adds.

Urban holds an appointment as the deputy director of the Inorganic Nanostructures Facility at the Berkeley Lab Molecular Foundry. The MF is a DOE Nanoscale Science Research Center (NSRC).

“Discovering new materials that could help us find a more sustainable energy solution is at the core of the Department of Energy’s mission. Our lab provides outstanding experiments to support this mission with great success,” adds Berkeley Lab expert Christian Kisielowski.

“We confirmed the presence of hydrogen in this material through time-dependent spectroscopic investigations with the TEAM 0.5 microscope. This investigation suggests that even direct imaging of hydrogen columns in such materials can be attempted using the TEAM microscope,” he concludes.