Figure 1: (d) Raman spectrum of few-layer graphene on Ni. (e) XPS of Ni 2p3/2 region of sputtered Ni (Ni/NiOx) and Ni after multilayer graphene growth (Ni/FLG), with peak fitting indicating metallic nickel (NiM) and nickel oxide (NiOx). (f) Magnetic moment measured at room temperature by DC-mode SQUID magnetometry of graphene-passivated Ni films for magnetic fields parallel and perpendicular to the plane of the film.

Figure 2: (b) Comparison of hole injection into F8BT from graphene-passivated Ni and PEDOT:PSS bottom contacts, each using a top contact of MoO3 / Au. (c) Binding energy, referenced to the Fermi level, measured on a Ni/FLG sample by means of UPS (excitation light with energy = 21.21 eV). (d) Hole injection into P3HT from graphene-passivated Ni, with MoO3 /Au top contact.

Figure 3: Current density hysteresis as a function of voltage for hole injection into F8BT using (a) unprotected sputtered Ni electrodes and (b) graphene-passivated Ni.