Materials challenges for hydrogen storage

Undesirable climate changes due to excessive anthropogenic CO2 emissions are of critical concern. Hydrogen as a clean energy carrier holds great promise in mitigating the problems. However, storing sufficient amount of hydrogen safely and practically poses large technical challenges, associated with materials properties that depend strongly on structure, chemistry and reaction path. Mechanical milling and chemical additions are effective in modifying various hydride systems. Considerable progresses have been achieved in improving thermodynamic and kinetic properties for hydrogen sorption. A final step to meet the technical challenges may rest with hybrid systems that can make use of modified physi- and chemi-sorptions, guided by computational simulations.