Hydrogen as a clean renewable and environmentally friendly energy source with high calorific value is considered to be of great importance to overcome present problem of energy crisis and environmental pollution. Aluminum-water reaction is proved to be one of the most dominant methods among numerous hydrogen generation ways. The paper focuses on the research progress of the technology of hydrogen generation from the hydrolysis of aluminum based materials in recent years. Hydrogen generation in-situ by Al-water reaction is a promising hydrogen storage and transportation way. However, the dense oxide layer on the surface of Al particles hinders the reaction of aluminum with water, making it difficult to produce hydrogen at room temperature and standard atmospheric pressure. In order to fully explore and utilize hydrogen energy, a variety of additives (such as alkali, metal hydride, metallic oxide, inorganic salt, metal and so on) are used for preparing aluminum-based materials. Generally, the preparation methods of the materials include sintering, smelting, ball-milling and other advance techniques. Research results have demonstrated that the above methods are able to effectively activate Al and achieve the aluminum-water reaction at low ambient temperature with short induction time, fast hydrogen production rate and high conversion rate. It may provide H₂ on board for fuel cells vehicles.

Contents
1 Introduction
2 Methods of hydrogen generation from aluminum hydrolysis
2.1 Al hydrolysis under alkali condition
2.2 Al-metal hydride composite hydrolysis
2.3 Al-metallic oxide composite hydrolysis
2.4 Al-inorganic salt composite hydrolysis
2.5 Al-metal alloy hydrolysis
3 Conclusion and outlook