Aromatic structure degradation of single layer graphene on an amorphous silicon substrate in the presence of water, hydrogen and Extreme Ultraviolet light

摘要

In this paper we study the reaction of water and graphene under Extreme Ultraviolet (EUV) irradiation and in the presence of hydrogen. In this work, single layer graphene (SLG) on amorphous Si as an underlying substrate was dosed with water (0.75 mL) and exposed to EUV (lambda = 13.5 nm, 92 eV) with partial pressures of H-2 in the background. The results show that the aromatic structure of graphene, when exposed to EUV and H-2, breaks down into aryl ketones and enols of 1,3 di-ketone. Infrared (IR) spectroscopy shows that SLG oxidizes, with increasing H-2 pressure leading to the grain boundary edges of graphene forming ketones and carboxylic acids. In situ and post exposure analyses also reveal that EUV exposure reduces the sp(2) content of the graphene layer, with the sp(3) content increasing, resulting in a more defective graphene layer. (C) 2017 Elsevier B.V. All rights reserved.