VATIS UPDATE Article

The US Department of Energy’s (DOE) Energy Materials Network (EMN) consortium approach to accelerate material discovery and development is starting to pay off. Through theory and experimentation, scientists at Lawrence Livermore National Laboratory (LLNL), the United States, have discovered the key mechanism by which magnesium diboride (MgB2) absorbs hydrogen and provided key insights into the reaction pathway that converts MgB2 to its highest hydrogen capacity form, magnesium borohydride (Mg(BH4)2).

Mg(BH4)2 is a particularly promising hydrogen storage material because of its high hydrogen content and attractive thermodynamics. “The insights provided by our study are an important step toward unlocking the potential of this material for solid-state hydrogen storage,” said Keith Ray, at LLNL. Storage of hydrogen is one of the critical enabling technologies for hydrogen-fueled transportation systems as well as grid resiliency, energy storage and use of diverse domestic resources across sectors, which can reduce oil dependency.

In the new study, the team took an important step toward understanding and improving these shortcomings. They found that in the initial stages of hydrogen exposure, MgB2 can hydrogenate to Mg(BH4)2 without the formation of intermediate compounds. Since these intermediates are known to inhibit the speed at which a hydrogen vehicle can be refueled, the possibility of avoiding them is an important development toward making MgB2 practically viable.