Hydrogen production for micro-fuel-cell from activated Al–Sn–Zn–X (X: hydride or halide) mixture in water

A systematic investigation of hydrogen production from milled Al–Sn–Zn–X (X: hydride or halide) mixtures in pure water was performed at room temperature. The hydrolysis mechanism of the mixtures was based on the work of micro-galvanic cell between aluminum and tin in water where aluminum reacted with water to generate AlOOH (Boehmite) and hydrogen. It was found that many effects such as milling time, temperature, additives and mass ratio had a significant role in the hydrogen production rate, especially that of the additives (hydride or halide) led to reduction of crystallite size and accumulation of uniform mixing. They also produced a lot of heat and the conductive ions which simulated the work of micro-galvanic cell. The milled Al–Sn–Zn–X (X: hydride or halide) mixtures had high reactivity and Al–Sn–Zn–MgH2 mixture produced 790 mL g−1 hydrogen in 5 min of the hydrolysis reaction with the activation energy of 17.570 kJ mol−1, corresponding to 7.04 wt.% hydrogen excluding water mass. Therefore, a new method of CO2 free and safe hydrogen production for micro-fuel-cell was obtained from the activated aluminum alloys in water.