SUMMARY Hydrogen generation by the reaction of pure Al powder in water with the addition of Al(OH)3, γ‐Al2O3, α‐Al2O3, or TiO2 at mild temperatures was investigated. It was found that the reaction of Al with water is promoted and the reaction induction time decreases greatly by the above hydroxide and oxides. X‐ray diffraction analyses revealed that the hydroxide and oxide phases have no any change during the Al–water reaction, indicating that they are just as catalysts to assist the reaction of Al with water. A possible mechanism was proposed, which shows that hydroxide and oxides could dissociate water molecules and promote the hydration of the passive oxide film on Al particle surfaces. Copyright © 2013 John Wiley & Sons, Ltd.

A facile route was used to modify Al particle surfaces by putting Al particles into an Al(OH) 3 suspension, which was produced by the reaction of Al powder with water under vacuum at a mild temperature, then drying and heat-treating under vacuum at elevated temperature. The modified Al powder has a good reaction activity with water to generate hydrogen, and its reaction rate depends on the sizes of Al particles used to produce Al(OH) 3 suspension. The reaction induction time of the modified Al powder prepared using the Al(OH) 3 suspension produced by the reaction of Al with water is obviously shorter than that prepared using the Al(OH) 3 suspension formed by the direct addition of a commercial Al(OH) 3 powder, because the in situ formed Al(OH) 3 has a finer microstructure. As the present method has no complicated processing procedure and the Al-water reaction byproduct can be reused to modify Al, it is an economically viable way to fabricate the activated Al powder for commercial applications.