Synchronously Producing H2 and Purifying Methyl Orange-Polluted Water through the Reaction of an Al–GaInSn Alloy Plate and H2O

Hydrogen gas (H₂) as a fuel has the advantages of high energy density (122 kJ g^-1) and zero carbon emissions. To meet the growing demand for H₂ in the future, green, efficient, and convenient production technologies must be developed. The Al-H₂O reaction, which produces H₂ by reacting aluminum (Al) with water (H₂O), is considered a rapid method for producing H₂. However, Al-H₂O creates a protective oxide layer on the surface of Al, preventing the production of H₂. In this study, we developed a simple method for forming Al-GaInSn alloy by brushing GaInSn-Al₂O₃ grease onto an Al plate to form an Al/GaInSn-Al₂O₃/Al sandwich structure. Al₂O₃ in the sample supports GaInSn, prevents the leakage of GaInSn, and promotes its penetration into the Al lattice to form Al-GaInSn alloy. By forming a liquid phase within the alloy, GaInSn increases the accessibility of Al to the reaction. As a result, the Al-GaInSn alloy can rapidly react with pure H₂O to produce H₂ at room temperature conditions, with yields as high as ∼93.2%. It was interesting to find that dye-polluted water (methyl orange) could be synchronically purified by the Al-H₂O reaction at the same time.