Reactivity of solvated electrons in ionic liquid interacting with low-pressure plasmas

Abstract

We employed charge transfer to the solvent (CTTS) transition to examine the reactivity of solvated electrons in ionic liquid interacting with plasmas. A dye laser pulse at 225 nm was injected into N,N,N-trimethyl-N-propylammonium bis (trifluoromethylsulfonyl) imide with the addition of potassium iodide, which was irradiated with low-pressure plasmas, and the reaction frequency of the solvated electrons produced by the CTTS transition was measured by optical absorption spectroscopy. It was observed that the reaction frequency of solvated electrons was enhanced by plasma irradiation. The enhanced reaction frequency was more remarkable by irradiation of a nitrogen plasma than argon and oxygen plasmas. In addition, a higher reaction frequency was observed at a closer distance from the plasma–liquid interface. The UV–vis absorbance spectrum of the ionic liquid was changed by plasma irradiation, indicating the production of unknown species which had a high reaction frequency with solvated electrons in the ionic liquid.