Effect of Electric Fields on Gamma Radiolysis of Methanol Vapor

Abstract

Electric fields were applied during the irradiation of methanol vapor up to voltages necessary to cause secondary ionization. The yields per ion pair of 3.00±0.02, 0.39±0.02, and 0.120±0.003 were estimated for hydrogen, carbon monoxide, and methane respectively by relating the product yields to the saturation ion current measured during the irradiation. The hydrogen yields decreased in the saturation current region, while the carbon monoxide and the methane yields remained nearly constant. The reduction of hydrogen yield may be ascribed to a suppression of dissociative electron-capture process CH3OH+e→CH3O−+H by a fast electronabsorption to the anode. The contribution of molecular or hot hydrogen atom process to the formation of hydrogen was found to increase with an increase of the electric field strength.