Highly improved with hydrogen storage capacity and fast kinetics in Mg-based nanocomposites by CNTs

Magnesium has shown a great potential in effective hydrogen storage due to their advantages of high volumetric and gravimetric hydrogen storage capacity. However, the use in fuel cell is limited by high dehydrogenation temperature and low sorption kinetics. Addition of carbon nanotubes (CNTs) in ball milling process produce magnesium powders in a nanocrystalline form, which gives remarkable improvement of absorption kinetics. With the addition of FeTi catalysts and CNTs-assisted milling, Mg based alloys performs fast hydriding kinetics reaching 6.6 wt.% only in 1 min at 150 °C. The grain size of Mg-based nanocomposites is about 50 nm from a direct evidence of TEM and XRD patterns. These results are promising for the application of magnesium materials for hydrogen storage. It is believed that smaller grain size and FeTi catalysts play an important role in improving the H2 absorption kinetics of Mg.

► Ball-milling of magnesium-based hydrides absorption temperature decrease at 150 °C. ► CNTs additives reduce grain size by the distinct thermo-mechanical properties. ► FeTi catalyst-doped Mg by ball milling also improves the hydrogenation kinetics.