Hydrogen gas evolution from alumina nanoparticles dispersed in water irradiated with gamma-ray

Hydrogen gas evolution induced by gamma-ray irradiation of nanoparticles di spersed in aqueous solution was studied by measuring hydrogen yields from T iO2, alpha- and gamma-Al2O3 nanoparticles. Hydrogen gas was detected by a g as chromatograph after an irradiation with Co-60 gamma-ray of the sample so lution in a closed vial at room temperature. TiO2 nanoparticles, a highly p hoto-catalysis mainly in anatase structure with average diameter of 21 nm, was found to have a relatively low evolution yield, about three times of th e back ground hydrogen evolution due to the water radiolysis, while the alp ha- and gamma-Al2O3 showed a much higher yield, 7-8 times of the background , depending on the total dose and dose rate of the gamma-ray. (C) 1999 Acta Metallurgica Inc.