Enhancement of Hydrogen Evolution Yield from Water Dispersing Nanoparticles Irradiated with Gamma-Ray

Effects of alumina powder characteristics on H2 and H2O2 production yields in γ-radiolysis of water and 0.4 M H2SO4 aqueous solution

“…In general, the H 2 yields apparently increased with increasing specific surface area of the alumina powders. This trend of the results is qualitatively similar to the result of the nanoparticle of TiO 2 [4] and the results of silica gels and TiO 2 [5]. Thus, the crystal structures apparently gave a minor effect on the H 2 yields for pure water.…”

“…To the best of the authors' knowledge, the detailed reports regarding the oxide characteristic effects on H 2 production are only few. Some limited data about the dependence of oxide surface area on H 2 production yields are available for water vapor adsorbed on ZrO 2 powder surface [3], water containing TiO 2 powder [4], and SiO 2 powder [5]. For the study of powder characteristics on g-radiolysis, aluminum oxide is a suitable material because it has many types of alumina powders to have various crystal structures and specific surface areas [6].…”

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

“…Concerning the role of chemisorbed water on oxide surface in order to enhance H 2 production yields, the discussion has been made from a viewpoint of the energy transfer from the oxide to water, for example, by an exciton model [12][13][14][15]. It has been pointed out that it is not the primary surface area of the nanopowder oxides but the agglomerated surface area which contributed to the increased H 2 production [16]. The water and metal systems were also studied from a viewpoint of secondary electron emission from metals [17].…”

“…It is known that electrons, which act as a reducing agent, contribute to the formation of H 2 gas [6][7][8][9]. In fact there have been reports of the enhanced H 2 formation as well as of reduction of ions due to the coexistence of solids and water [11][12][13][14][15][16][17].…”

Hydrogen Gas Generation from the Water by Gamma-Ray Radiolysis with Pre-Irradiated Silica Nanoparticles Dispersing

“…In the case when the oxide nanoparticles such as SiO 2 , TiO 2 , Al 2 O 3 or ZrO 2 disperse in the water the enhancement of the hydrogen gas generation has been observed. [1][2][3][4][5][6] However, the cause of the enhancement is not obvious so far. This would be due to the fact that the irradiation effects on the water and the nanoparticles have not been distinguished.…”