Hydrogen is considered a promising alternative to fossil fuels due to its clean combustion. The only emission from hydrogen is water vapor. However, the dream of a “hydrogen economy” where hydrogen is a viable alternative to fossil fuels is hampered by difficulties in finding ways to store hydrogen safely.
The Berkeley Lab scientists’ new material is a composite of nanoparticles of magnesium metal sprinkled through a matrix of polymethyl methacrylate. Polymethyl methacrylate is a polymer related to Plexiglas and lends the material a bit of pliancy and flexibility.
The pliable nanocomposite rapidly absorbs and releases hydrogen at modest temperatures without oxidizing the metal. The scientists believe this makes the material ideal for hydrogen storage, batteries and fuel cells.
The work involved cooperation with several facilities of the Department of Energy’s Office of Science located at Berkeley. Jeff Urban, deputy director of the Inorganic Structures Facility at the Molecular Foundry, a nanoscience center, led a team that developed the material.
Mr. Durban then turned to the National Center for Electron Microscopy, to use their TEAM 0.5 microscope to observe how the individual magnesium nanocrystals dispersed throughout the polymer matrix.
«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,» said Christian Kisielowski, co-author of the paper on the new material which appears in the journal Nature Materials.
The team is now working with Energy and Environmental Technologies Division of Berkeley Lab to study the uptake and release of hydrogen in the nanocomposite material.
«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,» says Mr. Urban.
The team is also looking into the application this new material could have in other areas of energy research.
Last year, a team of researchers from the Rice University in Huston, Texas developed a material called metallacarborane for hydrogen storage.
Much like the Berkeley Lab material, the one developed by Rice was a combination of different elements – boron, carbon and metal atoms.
The Rice material was said to have the potential to hold up to 8.8 percent of its weight in hydrogen atoms.
