Regensburg 2019 – wissenschaftliches Programm
MM 22.3: Vortrag
Mittwoch, 3. April 2019, 10:45–11:00, H43
6Mg(NH2)/9LiH/LiBH4: Molecular Dynamics and Hydrogen Diffusion — •Neslihan Aslan1,2, Wiebke Lohstroh2, Sebastian Busch1, Claudio Pistidda1, Klaus Pranzas1, and Martin Müller1 — 1Helmholtz-Zentrum Geesthacht, Germany — 2Heinz Maier-Leibnitz Zentrum, TUM, Garching, Germany
Methods to store hydrogen are e.g. physical technologies (compression) or chemical bonding in metal hydrides. Within the complex hydrides, the metal amides Mg(NH2)2-LiH have recently gained in importance. They have good hydrogen storage properties with high capacity (ca. 4 wt%) and good reversibility. The drawback of these materials is the high kinetic barrier for hydrogenation, which results in a long loading time. This can be overcome with the addition of LiBH4. So far Mg(NH2)2-LiH-LiBH4 is an outstanding candidate for hydrogen storage. Interestingly, some compositions can even reach operation temperatures below 100 °C and the desorbed products contain amongst others liquid phases. The hydrogen uptake and release properties of this system are well characterized in terms of capacity, kinetics and phase composition, but the basic mechanism how the reaction takes place and why it has these excellent storage facilities is still unknown. With 6Mg(NH2)/9LiH/LiBH4 we want to understand the system and the reaction mechanism. We will present first data of neutron scattering experiment using quasielastic scattering at TOFTOF to study hydrogen diffusion of the desorbed and absorbed state, as well as small angle neutron scattering to study particle sizes to gain further insight on the hydrogenation/dehydrogenation mechanism.