Effect of defects on the intrinsic strength and stiffness of graphene

• Published in: Nature communications 2014-01, Vol.5 (1), p.3186-3186, Article 3186
• Main Authors: Zandiatashbar, Ardavan, Lee, Gwan-Hyoung, An, Sung Joo, Lee, Sunwoo, Mathew, Nithin, Terrones, Mauricio, Hayashi, Takuya, Picu, Catalin R., Hone, James, Koratkar, Nikhil
• Format: Article
• Language: English
• Subjects: 639/301/357/918/1053; Defects; Engineering; Graphene; Humanities and Social Sciences; Materials science; Mechanical properties; Microscopy; multidisciplinary; Plasma; Science; Science (multidisciplinary)
• ISSN: 2041-1723; 2041-1723
• DOI: 10.1038/ncomms4186

It is important from a fundamental standpoint and for practical applications to understand how the mechanical properties of graphene are influenced by defects. Here we report that the two-dimensional elastic modulus of graphene is maintained even at a high density of sp 3 -type defects. Moreover, the breaking strength of defective graphene is only ~14% smaller than its pristine counterpart in the sp 3 -defect regime. By contrast, we report a significant drop in the mechanical properties of graphene in the vacancy-defect regime. We also provide a mapping between the Raman spectra of defective graphene and its mechanical properties. This provides a simple, yet non-destructive methodology to identify graphene samples that are still mechanically functional. By establishing a relationship between the type and density of defects and the mechanical properties of graphene, this work provides important basic information for the rational design of composites and other systems utilizing the high modulus and strength of graphene. Defects are known to affect the mechanical properties of materials. Here, the authors find that sp 3 -type defects in graphene have a negligible effect on stiffness and cause only a slight reduction in failure strength, while vacancy-type defects are much more degrading.