Pulse-radiolysis study on the reaction of hydrated electron in aqueous solution in the presence of colloidal silica

Kumagai, Yuta   ; Nagaishi, Ryuji ; Yamada, Reiji; Muroya, Yusa*; Katsumura, Yosuke*

In radiolysis of mixture of water and solid oxides, reactions of hydrated electron are considered as a possible source of excess production of H. In this study transient kinetics of hydrated electron in aqueous solution containing nano-sized colloidal silica was studied using pulse-radiolysis technique. The decay of hydrated electron became slower by the addition of colloidal silica. However in aqueous solution containing -butanol, where the reaction of hydrated electron with hydroxyl radical is inhibited, the addition of colloidal silica had no significant effect on the kinetics of hydrated electron. The results suggest that the effect of colloidal silica on the decay of hydrated electron was due to the reaction of colloidal silica with hydroxyl radical. Therefore the coexistence of colloidal silica was not expected to induce an effective reaction pathway to produce H from hydrated electron.