In-situ S/TEM Visualization of Metal-to-Metal Hydride Phase Transformation of Magnesium Thin Films

In our quest for a solution to drive the decarbonization of our society and economy, hydrogen shows unique properties as a zero-emission fuel, energy storage solution, and chemical feedstock [1]. However, compact storage remains a scientific and technological challenge. Safely storing hydrogen, e.g., in the solid form of metal hydrides, has many advantages, but further improving its storage properties requires a thorough understanding of the metal-to-metal hydride phase transformation at the atomic level [1]. Although many techniques have been applied to understand these phase transformations, in-situ visualization of the transformation process is essential for a quantitative understanding [2,3]. For example, stress/strain, defects, and intermediate phase evolution during metal-to-metal hydride phase transformation are crucial to interpret the hydrogen sorption properties [4].