SEM images of the as-received commercial MgH2 and deposits after its hydrolysis in 1 wt.% aqueous solutions of organic acids are shown in Figure ). The morphology of the as-received MgH2 (Figure (a)) shows irregular and flaky particle orientation. The morphology of the residues after hydrolysis (Figure )) exhibits similar flake-like structure with a continuous smooth surface; the images show significant decrease in number or complete disappearance of small (~0.1 m) particles observed in the starting material (Figure XRD patterns of the studied samples are presented in Figure ) and Figure ).