Controllable synthesis of 2D TiH2 nanoflakes with superior catalytic activity for low-temperature hydrogen cycling of NaAlH4

Nanosized titanium compounds are particularly effective in catalyzing hydrogen cycling by NaAlH4. Titanium hydride (TiH2), as a catalyst, is highly interesting since it contributes addition to active Ti. However, has been challenging fabricate nanosized TiH2 due the strong affinity of Ti with oxygen. Herein, nanoflakes lateral size ~10 nm and thickness ~1 successfully synthesized through novel facile one-pot solvothermal process. In an anhydrous THF solution, LiH reacts TiCl4 rapidly at 100 °C forming LiCl. The newly formed nucleates grows epitaxially on graphene surface well-matched lattice parameters, giving rise formation nanoflakes. Both theoretical calculations experiments reveal generation Cl· radicals unsaturated CC bonds when THF, which promotes TiH2. nanoflake-like enables outstanding storage performance NaAlH4, i.e., full dehydrogenation 80 hydrogenation 30 under bar H2, practical capacity 4.9 wt%, never reported before.