Tuning the hydrogen storage properties of TiFe clusters via Zr substitution

Abstract

Titanium-Iron alloy is a well-known material for hydrogen storage applications at room temperature. The limitations of TiFe alloy is its low hydrogen storage capacity, higher activation temperature, and pressure. In order to improve the hydrogen adsorption of TiFe alloy, TiFe clusters with Zr atom as a dopant are investigated using first-principle calculations. The structure of the Zr-substituted and unsubstituted clusters was optimized and it is found that the binding energy of the Zr-substituted TiFe clusters is higher than TiFe clusters, thus, the doping Zr atom stabilizes the TiFe clusters. Hydrogen adsorption over Zr doped TiFe cluster is investigated, where, Zr is revealed to be an active site for hydrogen adsorption except Ti 3 Zr 1 Fe 4 cluster. Hence, Zr substitution stabilizes the TiFe clusters and hydrogen storage properties were tuned by the introduction of the Zr atom.