1. MgH2 nanoparticles confined in reduced graphene oxide pillared with organosilica: a novel type of hydrogen storage material
- Author
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Yan, Feng, Alfonsín, Estela Moreton, Ngene, Peter, de Graaf, Sytze, De Luca, Oreste, Cao, Huatang, Spyrou, Konstantinos, Lu, Liqiang, Thomou, Eleni, Pei, Yutao, Kooi, Bart J., Gournis, Dimitrios P., de Jongh, Petra E., and Rudolf, Petra
- Subjects
Condensed Matter - Materials Science - Abstract
Hydrogen is a promising energy carrier that can push forward the energy transition because of its high energy density (142 MJ kg-1), variety of potential sources, low weight and low environmental impact, but its storage for automotive applications remains a formidable challenge. MgH2, with its high gravimetric and volumetric density, presents a compelling platform for hydrogen storage; however, its utilization is hindered by the sluggish kinetics of hydrogen uptake/release and high temperature operation. Herein we show that a novel layered heterostructure of reduced graphene oxide and organosilica with high specific surface area and narrow pore size distribution can serve as a scaffold to host MgH2 nanoparticles with a narrow diameter distribution around ~2.5 nm and superior hydrogen storage properties to bulk MgH2. Desorption studies showed that hydrogen release starts at 50 {\deg}C, with a maximum at 348 {\deg}C and kinetics dependent on particle size. Reversibility tests demonstrated that the dehydrogenation kinetics and re-hydrogenation capacity of the system remains stable at 1.62 wt.% over four cycles at 200 {\deg}C. Our results prove that MgH2 confinement in a nanoporous scaffold is an efficient way to constrain the size of the hydride particles, avoid aggregation and improve kinetics for hydrogen release and recharging.
- Published
- 2023