▎ 摘　　要

The coadsorption of potassium with water at 100 K on graphene/Pt(111) has been studied by high-resolution electron energy loss spectroscopy. The adsorption of alkali metals induces water splitting and the formation of C-H and C-OH groups. Such finding is of great interest for tailoring graphene-Pt electro-catalysts. Furthermore, the alkali-promoted dissociation of water molecules offers the possibility to attain a partial hydrogenation of the graphene sheet even at low temperature. (C) 2013 American Institute of Physics. [http://dx.doi.org/10.1063/1.4788619]