| AVS 57th International Symposium & Exhibition | |
| Graphene Focus Topic | Tuesday Sessions |
| Session GR+TF-TuM |
| Session: | Characterization, Properties, and Applications |
| Presenter: | X. Zhang, Bielefeld University, Germany |
| Authors: | X. Zhang, Bielefeld University, Germany C.T. Nottbohm, Bielefeld University, Germany A. Turchanin, Bielefeld University, Germany A. Beyer, Bielefeld University, Germany A. Gölzhäuser, Bielefeld University, Germany |
| Correspondent: | Click to Email |
We report on the fabrication and mechanical characterization of novel graphenoid nanomembranes with a thickness of approximately 1 nm. The nanomembranes are prepared from electron cross-linked aromatic self-assembled monolayers (SAMs). The membranes are then transferred to window-substrates (Si) for mechanical characterization. Bulge testing of such freestanding nanomembranes within an atomic force microscope is utilized to investigate their mechanical properties.
A series of biphenyl-based molecules were used to prepare the nanomembranes, such as carbonitrile-biphenyl-trimethoxysilyl (CBPS), biphenyl-thiol (BPT) and nitro-biphenyl-thiol (NBPT). Biphenyl-based nanomembranes have elastic moduli ranging from 6 to 12 GPa. They display outstanding performance in the ultimate tensile strength with values of 400 to 500 MPa, which is several times higher than the values of other carbon based membranes. Furthermore, annealing of the cross-linked nanomembranes in ultra high vacuum systematically increase of the Young’s moduli from 10 GPa to ~45 GPa for an annealing temperature of ~1000 K. Strain relaxation lowers the residual strain from 0.9 % to ~0.35 % for temperatures of 800 K and above. This is caused by a structural transformation in which the nanomembrane is converted into nanocrystalline graphene.