Enhancing the Adhesion of Graphene to Polymer Substrates by Controlled Defect Formation

Abstract

The mechanical integrity of composite materials depends primarily on the interface strength and the defect density of the reinforcement which is the provider of enhanced strength and stiffness. In the case of graphene/ polymer nanocomposites which are characterized by an extremely large interface region, any defects in the inclusion (such as folds, cracks, holes etc.) will have a detrimental effect to the internal strain distribution and the resulting mechanical performance. This conventional wisdom, however, can be challenged if the defect size is reduced beyond the critical size for crack formation to the level of atomic vacancies. In that case, there should be no practical effect on crack propagation and depending on the nature of the vacancies the interface strength may be in fact increase. In this work we employed argon ion (Ar+) bombardment and subsequent exposure to hydrogen (H2) to induce (as revealed by X-ray & Ultraviolet photoelectron spectroscopy (XPS/UPS) and Raman spectroscopy) passivated atomic single vacancies to CVD graphene. The modified graphene was subsequently transferred to PMMA bars and the morphology, wettability and the interface adhesion of the CVD graphene/PMMA system were investigated with Atomic Force Microscopy technique and Raman analysis. The results obtained showed clearly an overall improved mechanical behavior of graphene/polymer interface, since an increase as well a more uniform shift distribution with strain is observed. This paves the way for interface engineering in graphene/polymer systems which, in pristine condition, suffer from premature graphene slippage and subsequent failure.

References in corpus (16)

• Electric Field Effect in Atomically Thin Carbon Films
• Probing the Nature of Defects in Graphene by Raman Spectroscopy
• Uniaxial Strain in Graphene by Raman Spectroscopy: G peak splitting, Gruneisen Parameters and Sample Orientation
• Control and Characterization of Individual Grains and Grain Boundaries in Graphene Grown by Chemical Vapor Deposition
• Structure and electronic transport in graphene wrinkles
• Probing the Intrinsic Properties of Exfoliated Graphene: Raman Spectroscopy of Free-Standing Monolayers
• Surface energy engineering of graphene
• Subjecting a graphene monolayer to tension and compression
• Multiply Folded Graphene
• Raman 2D-Band Splitting in Graphene: Theory and Experiment
• Reliably Counting Atomic Planes of Few-Layer Graphene (n>4)
• Electronic properties of curved graphene sheets
• The control of graphene double-layer formation in copper-catalyzed chemical vapor deposition
• Wrinkled few-layer graphene as highly efficient load bearer
• Stress and charge transfer in uniaxially strained CVD graphene
• Stiffening graphene by controlled defect creation

Cited by in corpus (2)

• Stress-transfer from polymer substrates to monolayer and few-layer graphenes
• Wettability of graphene by molten polymers