The proposed research project aims at determining proper thermodynamic conditions for reversible charging of the icosahedral Ti-Zr-Ni-(Cr,Cu) nano-alloys with hydrogen/deuterium. In order to achieve this, the in-situ neutron diffraction experiments under deuterium pressure are required. The obtained diffraction patterns recorded as functions of pressure and temperature will give the first-hand information about formation of the icosahedral deuterides, stability boundaries and reaction kinetics. On the other hand, structural studies of the atomic arrangements in quasicrystalline hydrides are of the utmost importance for understanding the mechanisms of a hydrogen uptake that signals the further ways of development of solid-state hydrogen reservoirs.