Description:
<jats:title>Abstract</jats:title><jats:p>The system Mg(NH<jats:sub>2</jats:sub>)<jats:sub>2</jats:sub> + 2LiH is considered as an interesting solid-state hydrogen storage material owing to its low thermodynamic stability of ca. 40 kJ/mol H<jats:sub>2</jats:sub> and high gravimetric hydrogen capacity of 5.6 wt.%. However, high kinetic barriers lead to slow absorption/desorption rates even at relatively high temperatures (>180 °C). In this work, we investigate the effects of the addition of K-modified Li<jats:sub>x</jats:sub>Ti<jats:sub>y</jats:sub>O<jats:sub>z</jats:sub> on the absorption/desorption behaviour of the Mg(NH<jats:sub>2</jats:sub>)<jats:sub>2</jats:sub> + 2LiH system. In comparison with the pristine Mg(NH<jats:sub>2</jats:sub>)<jats:sub>2</jats:sub> + 2LiH, the system containing a tiny amount of nanostructured K-modified Li<jats:sub>x</jats:sub>Ti<jats:sub>y</jats:sub>O<jats:sub>z</jats:sub> shows enhanced absorption/desorption behaviour. The doped material presents a sensibly reduced (∼30 °C) desorption onset temperature, notably shorter hydrogen absorption/desorption times and reversible hydrogen capacity of about 3 wt.% H<jats:sub>2</jats:sub> upon cycling. Studies on the absorption/desorption processes and micro/nanostructural characterizations of the Mg(NH<jats:sub>2</jats:sub>)<jats:sub>2</jats:sub> + 2LiH + K-modified Li<jats:sub>x</jats:sub>Ti<jats:sub>y</jats:sub>O<jats:sub>z</jats:sub> system hint to the fact that the presence of <jats:italic>in situ</jats:italic> formed nanostructure K<jats:sub>2</jats:sub>TiO<jats:sub>3</jats:sub> is the main responsible for the observed improved kinetic behaviour.</jats:p>