Pacific Rim Symposium on Surfaces, Coatings and Interfaces (PacSurf 2014)
    Thin Films Wednesday Sessions
       Session TF-WeP

Paper TF-WeP38
Probing Ni(111)-graphene interface using Raman spectroscopy

Wednesday, December 10, 2014, 4:00 pm, Room Mauka

Session: Thin Films Poster Session
Presenter: Guanjun Cheng, National Institute of Standards and Technology
Authors: G. Cheng, National Institute of Standards and Technology
I. Calizo, National Institute of Standards and Technology
A.R. Hight-Walker, National Institute of Standards and Technology
Correspondent: Click to Email
Theoretical simulations have shown that due to the hybridization of Ni d-electrons with the π-orbitals of graphene, graphene phonon dispersion is significantly altered and there is no Raman signal from graphene on Ni(111) due to the suppression of the Kohn anomaly (Nano Lett, 2010, 10, 4335-4340). In this work, we deposit Ni thin film by thermal evaporation onto mechanically exfoliated graphene,few-layer graphene (FLG), and graphite, and probe the Ni-graphene interface using Raman spectroscopy. When the sample is annealed in forming gas, Ni(111) thin film is produced on graphene, FLG, and graphite. We observe the disappearance of Raman signals from graphene underneath Ni(111) using a low power excitation laser and the re-appearance of Raman signals from graphene with a higher power excitation laser. This work provide direct experimental evidence for the strong interactions between Ni(111) and graphene.