Hydrogen generation from the reaction of Al-based composites activated by low-melting-point metals/oxides/salts with water

Aluminum metal needs to be activated to improve its hydrogen generation properties by using an inexpensive way for its wide adoption. Al-based composites activated by low-melting-point metals, oxides, and salts were prepared by high-energy ball milling and characterized using a range of instrumental analysis techniques. Uniform and orthogonal designs were chosen to optimize the components and mechanical alloying parameters of the Al-based composites, respectively, for improving their hydrogen generation properties and reducing cost. The results suggest that the Al-1.0 wt%Ga-1.5 wt%In-3.0 wt%SnCl 2 -1.0 wt%Bi 2 O 3 composite prepared using the parameters A 4 B 1 C 3 D 2 exhibited a hydrogen yield of 1172.3 mL g −1 and maximum hydrogen generation rate of 1030.5 mL min −1  g −1 at 25 °C and atmospheric pressure. The activation energy (E a ) of the hydrolysis reaction was calculated to be 20.0781 kJ mol −1 . Moreover, according to the Tafel curves, the corrosion potential of Al-based composites in water becomes more negative compared with that of pure Al, which could improve its hydrogen generation properties. Therefore, this new material could be used as hydrogen sources for fuel cells.