Ion beam effects on electrical characteristics of proton conductive polymer

Abstract

Effect of MeV ion irradiation on the perfluorosulphonic polymer membrane was studied concerning with electrical characteristics. The DC electrical conductivity in dry condition increased of three orders of magnitude as a consequence of irradiation with MeV H and He ion beam at a fluence of 2×1013ions/cm2. The ion induced improvement of the conductivity was independent of the penetrating depth of the ions. The electron and gamma-ray irradiation showed similar enhancement of the conductivity when the same energy was deposited in the membrane. The optical absorption in the ultra-violet region increased in the ion irradiated membrane due to the formation of fluorocarbon and peroxy radicals, while the up-take of the water molecules were not found by the absorption in the infrared region. The ion irradiation may promote the dissociation of the water molecules at the surface and also improve the transport property of protons in the membrane.