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A new method of hydrogen generation from Al−Li−Sn alloy was studied in the present article. The hydrogen generation performance of the alloy could be regulated via composition design. The optimized Al−10 wt% Li−5 wt% Sn alloy yielded 1,329 ml g−1hydrogen with 100% efficiency and controllable hydrogen generation rate within 30 min at 298 K. Using X-ray diffraction, scanning electron microscopy, and Brunauer-Emmet-Teller analysis, the improved hydrogen generation performance mostly came from the AlLi and Li13Sn5phases distributed into Al matrix, which were helpful to decrease the particle size in the milling process. The phases acted as the initial reaction centers and stimulated Al hydrolysis in the hydrolysis process. There existed different hydrolysis processes, including chemical reaction of aluminum and water catalyzed by hydrolysis byproduct LiOH and electrochemical corrosion of Al and Li. The latter was based on the dual micro-galvanic cells between Al−Sn and Li−Sn from Al−Li13Sn5microstructure. Al−Li−Sn alloys had a potential application in portable hydrogen sources due to its high hydrogen generation density, high hydrogen purity, etc. The experimental data laid a foundation for hydrogen generator design. [ABSTRACT FROM PUBLISHER]

A method for obtaining hydrogen through the hydrolytic reaction of highly activated aluminum (Al) alloy is investigated. The optimized Al-3 wt.% Li-4 wt.% In-7 wt.% Zn alloy significantly improves the maximum hydrogen generation rate and amount (137 mL g-1 min-1 and 1,243 mL g-1, respectively). An efficiency of 100% was reached within 1 h at 298 K. The synergistic catalytic effects of Li, In, and Zn, which stimulated Al hydrolysis through the formation of micro galvanic cells of In-Li and Al-In-Zn alloys in water, were observed. The reactions were analyzed using X-ray diffraction, scanning electron microscopy, transmission electron microscopy, and hydrolytic experiments. The In-Li alloy functions as an initial active center and produces LiOH in water, which further stimulates and changes the hydrolytic process of the Al-In-Zn alloy. The effects of alloy composition, milling time, and hydrolytic temperature were considered and discussed. The results indicate that the hydrolytic reaction of Al-Li-In-Zn alloy in water might be feasible for the production of inexpensive, pure, and safe hydrogen for micro fuel cells. [ABSTRACT FROM AUTHOR]