The aim of this method is to propose a novel technology for metals and their alloys hydrogenation which combines the above-mentioned methods (1-4) and does not require using expensive catalysts (Pt and Pd) in the process of metal hydride synthesis. Furthermore, due to the synergetic combination of surface activation and high hydrogen pressure in a single device, a notably more efficient hydrogenation process may be achieved. The use of the proposed method enables forming hydrides of metals and their alloys up to ten times faster than using conventional methods.
This method is different from others because, at first, the hydrogen storage material (metals and their alloys) is covered with a thin 10-100 nm thick Ni layer and placed into an activation/hydrogenation chamber which is evacuated down to 10-2 Pa or lower vacuum. The chamber is filled with Ar or Ar+H2 gas mixture (possible hydrogen concentration is 0-99%) up to 0.1-15 Pa and Ar+H2 plasma is initiated. Next, Ni nanocatalyst clusters are formed on the surface of the hydrogenated material. After formation of Ni nanocatalytic particles the pressure must be switched from low vacuum (0.1-15 Pa) to high (10-300 bar) pressure without samples extraction to air and the temperature in the chamber are raised to up to several hundreds of degrees Celsius. Finally, hydrogen molecules, split into hydrogen atoms because of the interaction with Ni nanocatalysts, are transported from the activated surface of the hydrogenated material to the bulk through the grain boundaries, and a metal hydride is formed due to the interaction between neighbouring hydrogen atoms.