Rb and Cs deposition on epitaxial graphene grown on 6H-SiC(0001)

► Rb and Cs deposited on monolayer graphene gives rise to electron doping. ► Rb and Cs atoms do initially disrupt the bonds in graphene layer. ► None of these two alkali metals do intercalate into graphene and buffer layer. ► This is contrary to our study on Li where intercalation occurred after deposition.