London: Hydrogen has been touted as a promising alternative to fossil fuels since the 1970s due to its clean combustion.
But to replace the gasoline as a fuel, hydrogen must be safely and densely stored and easily accessed.
Limited by materials unable to leap these conflicting hurdles, hydrogen storage technology has lagged behind other clean energy candidates.
Now, scientists with the U.S. Department of Energy (DOE) Lawrence Berkeley National Laboratory (Berkeley Lab) have achieved a breakthrough in this regard.
They have designed a new composite material for hydrogen storage consisting of nanoparticles of magnesium metal sprinkled through a matrix of polymethyl methacrylate, a polymer related to Plexiglas.
This pliable nanocomposite rapidly absorbs and releases hydrogen at modest temperatures without oxidizing the metal after cycling—a major breakthrough in materials design for hydrogen storage, batteries and fuel cells.
“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,” said Jeff Urban, deputy director of the Inorganic Nanostructures Facility at the Molecular Foundry.
“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,” he added.
Urban and his colleagues used the TEAM 0.5 microscope to observe individual magnesium nanocrystals dispersed throughout the polymer.
“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 co-author Christian Kisielowski.
To investigate the uptake and release of hydrogen in their nanocomposite material, the team turned to Berkeley Lab`s Energy and Environmental Technologies Division (EETD), whose research is aimed at developing more environmentally friendly technologies for generating and storing energy, including hydrogen storage.
“This ambitious science is uniquely well-positioned to be pursued within the strong collaborative ethos here at Berkeley Lab. The successes we achieve depend critically upon close ties between cutting-edge microscopy at NCEM, tools and expertise from EETD, and the characterization and materials know-how from MSD,” said Urban.
The study is appearing in the journal Nature Materials and available in Nature Materials online.