Destabilization of magnesium hydride through interface engineering

Destabilization of magnesium hydride through interface engineering

Mooij, L.P.A.

Dam, B. (promotor)

Applied Sciences

Department of Chemical Engineering

2013-10-01

The aim of this thesis is to study the thermodynamics of hydrogenation of nanoconfined magnesium within a thin film multilayer model system. Magnesium hydride is a potential material for hydrogen storage, which is a key component in a renewable energy system based on hydrogen. In bulk form, magnesium hydride is very stable, which means that hydrogen is released only at elevated temperature. Furthermore, the kinetics of hydrogen sorption is slow, which further hampers the practical use of this hydrogen storage material. A solution to both these issues may be found in nanoconfinement. At the nanoscale, the contribution of the surface (or interface) energy starts to play a large role and potentially destabilizes magnesium hydride. The kinetics is expected to improve due to the increased surface area and shorter diffusion lengths. With a thin film model system, the confinement of magnesium can be directly controlled by changing the magnesium layer thickness, as well as by changing the interfacing materials of the magnesium layer. The effect of the interface energy and further effects from nanoconfinement such as nucleation and growth, mechanical anisotropy and alloying are all investigated. These findings provide valuable insights for the optimization of nanosized hydrogen storage systems, thus paving the road to thin layered nanostructures enabling hydrogen desorption at 1 bar at room temperature.

hydrogen storage
metal hydride
nanoconfinement
magnesium
interface energy

https://doi.org/10.4233/uuid:0d10c8b5-102a-4be7-9b3c-1d0aa434adf1

2013-10-01

9789461861849

Institutional Repository

doctoral thesis

(c) 2013 Mooij, L.P.A.