Hydrogen production in the γγ-radiolysis of aqueous sulfuric acid solutions containing Al2O3, SiO2, TiO2 or ZrO2 fine particles

Hydrogen production was studied in the 60Co γγ-radiolysis of aqueous H2SO4 solutions containing oxide powder of Al2O3, SiO2, TiO2 or ZrO2. The observed yields of final product H2 increased with relative amounts of oxide powder in the solutions and exhibited a particular H2SO4 concentration dependence, which was different for each oxide species and its amount. The addition of a small amount of CH3OH to a 0.4 M H2SO4 aqueous solution with oxide powder was quite effective for increasing the final product yields of H2. The obtained results revealed that heterogeneous systems composed of oxide powder and aqueous H2SO4 solution were more efficient for producing H2 molecules in γγ-radiolysis than homogeneous systems without oxides.