Hydrogen generation from hydrolysis of activated aluminum composites in tap water

Activated aluminum composites Al-X(X = Sn, Bi, Bi-Sn) were prepared by high-energy milling, and characterized by scanning electron microscope (SEM), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). Their hydrogen generation was systematically investigated in tap water. The experimental results suggest that the ternary Al-Bi-Sn composites show the better hydrolysis properties than binary composites Al-Bi and Al-Sn owing to the synergistic effect of metal Bi and Sn. The 3 h milled Al-7.5%Bi-2.5%Sn composite exhibits the highest hydrogen conversion yield with the maximum hydrogen generation rate of 9.5 mL s⁻¹ g⁻¹ at 35 °C. In addition, the effect of initial reaction temperature and water quality on the hydrolysis properties, the methods of protecting the activity of activated Al composites are discussed as well.