We have studied the mechanical properties of a few-layer graphene cantilever (FLGC) using atomic force microscopy (AFM). The mechanical properties of the suspended FLGC over an open hole have been derived from the AFM data. Force displacement curves using the Derjaguin-Müller-Toporov (DMT) and the massless cantilever beam models yield a Young modulus of E(c) approximately 37, E(a) approximately 0.7 TPa and a Hamakar constant of approximately 3 x 10( - 18) J. The threshold force to shear the FLGC was determined from a breaking force and modeling. In addition, we studied a graphene nanoribbon (GNR), which is a system similar to the FLGC; using density functional theory (DFT). The in-plane Young's modulus for the GNRs were calculated from the DFT outcomes approximately 0.82 TPa and the results were compared with the experiment. We found that the Young's modulus and the threshold shearing force are dependent on the direction of applied force and the values are different for zigzag edge and armchair edge GNRs.

Density functional study of strain effects on the electronic band structure and transport properties of the graphene nanoribbons (GNR) is presented. We apply a uniaxial strain (ε) in the x (nearest-neighbor) and y (second nearest-neighbor) directions, related to the deformation of zigzag and armchair edge GNRs (AGNR and ZGNR), respectively. We calculate the quantum conductance and band structures of the GNR using the Wannier function in a strain range from −8% to +8% (minus and plus signs show compression and tensile strain). As strain increases, depending on the AGNR family type, the electrical conductivity changes from an insulator to a conductor. This is accompanied by a variation in the electron and hole effective masses. The compression ε x in ZGNR shifts some bands to below the Fermi level (E f ) and the quantum conductance does not change, but the tensile ε x causes an increase in the quantum conductance to 10e 2 /h near the E f .For transverse direction, it is very sensitive to strain and the tensile ε y causes an increase in the conductance while the compressive ε y decreases the conductance at first but increases later.

We present a molecular dynamics simulation of chemical vapor deposition of graphene. Single layer graphene growth on a Ni (100) facet was studied at different substrate temperatures, C flow rates, and C flow energies. Results show that a single layer graphene film grows through a combined deposition mechanism on a Ni substrate, rather than by surface segregation. These simulations suggest that high quality graphene deposition is theoretically possible on Ni (100) facet under high flux energy.

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