Effect of the particle size evolution on the hydrogen storage performance of KH doped Mg(NH2)2 + 2LiH

• DOI: 10.1007/s10853-022-06985-4
• Publication Date: 2022-03-04T22:02:22Z
• Authors: Gökhan Gizer; Fahim Karimi; Claudio Pistidda; Hujun Cao; Julian A. Puszkiel; Yuanyuan Shang; Eike Gericke; Armin Hoell; P. Klaus Pranzas; Thomas Klassen; Martin Dornheim
• Keywords: Gravimetric analysis; Magnesium hydride; Cryo-adsorption; Particle (ecology)

Abstract In recent years, many solid-state hydride-based materials have been considered as hydrogen storage systems for mobile and stationary applications. Due to a gravimetric capacity of 5.6 wt% dehydrogenation enthalpy 38.9 kJ/mol H 2 , Mg(NH ) + 2LiH is potential material be coupled with PEM fuel cell devices. One the main challenges reduction temperature since this system requires high temperatures (~ 200 °C). The addition KH significantly decreases onset 130 °C. On one hand, stabilizes capacity. other reduced by 50% (from 4.1 2%) after first 25 cycles. work, particle sizes overall hydride matrix potassium-containing species are investigated during cycling. Relation between size evolution additive kinetics described using an advanced synchrotron-based technique: Anomalous small-angle X-ray scattering, which was applied time at potassium K-edge amide-hydride systems. outcomes from investigation show that, nanometric phases might located reaction interfaces, limiting coarsening. Average diameters nanoparticles double cycles 10 20 nm). Therefore, subsequent degrade. deterioration can minimized selecting lower absorption temperatures, mitigates growth, resulting in two times faster kinetics.