Small Ti clusters for catalysis of hydrogen exchange in NaAlH₄

Colloidal Ti has been synthesized following a method described in the literature. Extended x-ray absorption fine structure measurements indicate the presence of small colloidal entities, consisting of only a few core Ti atoms which are coordinated by O atoms from tetrahydrofuran (THF). The results can be explained by the proposed structure of Ti₁₃ · 6THF, in which the Ti cluster has the shape of a distorted icosahedron. The Ti colloid was used to prepare a functional nanocomposite by ball-milling the clusters with NaAlH₄. The nanocomposite showed superior hydrogen exchange kinetics when compared to the state of the art in the literature.