Transformation of Metallic Ti to TiH<sub>2</sub> Phase in the Ti/MgH<sub>2</sub> Composite and Its Influence on the Hydrogen Storage Behavior of MgH<sub>2</sub>
D. Pukazhselvan, K. S. Sandhya, Devaraj Ramasamy, A.L. Shaula, Duncan P. Fagg
Abstract
Abstract The current work explores the in‐situ formation of TiH 2 additive in a Ti/MgH 2 nanocomposite system. Mild mechanical milling leaves Ti chemically unchanged, while formation of stable TiH 2–x occurs upon strong mechanical milling. TiH 2–x further transforms to TiH 2 upon recycling the powder (dehydrogenation and subsequent hydrogenation) and lowers the activation energy of MgH 2 to 89.4 kJ (mol H 2 ) −1 [ E a of as‐received MgH 2 is 153 kJ (mol H 2 ) −1 ]. This work also reiterates that metallic Ti additive mixed MgH 2 requires strong mechanical milling for better H 2 ab/de‐sorption performance. The current observations support the view that lattice strain may be an important factor in the catalysis of additives incorporated MgH 2 hydrogen storage systems.