[Paper Review] Reversible electronic and mechanical properties of ripped graphene

J. Henry Hinnefeld, Stephen T. Gill+4 more|arXiv (Cornell University)|Jul 1, 2014

Graphene research and applicationsMaterials Science1 citations

TL;DR

This study demonstrates that micro-rips form in graphene when initially strained on elastomer substrates, but these rips reversibly open and close under repeated strain cycles. Despite initial degradation, electrical transport properties recover elastically, enabling robust, reversible electronic performance even after partial mechanical failure.

ABSTRACT

We examine the mechanical properties of graphene devices stretched on flexible elastomer substrates. Using atomic force microscopy, transport measurements, and mechanics simulations, we show that micro-rips form in the graphene during the initial application of tensile strain; however subsequent applications of the same tensile strain elastically open and close the existing rips. Correspondingly, while the initial tensile strain degrades the devices' transport properties, subsequent strain-relaxation cycles affect transport only moderately, and in a largely reversible fashion, yielding robust electrical transport even after partial mechanical failure.

Motivation & Objective

• To investigate the mechanical and electronic behavior of graphene under repeated tensile strain on flexible substrates.
• To understand the formation and evolution of micro-rips in graphene during initial and subsequent strain cycles.
• To evaluate the reversibility of electrical transport properties following mechanical rippability.
• To establish the feasibility of using rippable graphene in durable flexible electronic devices.

Proposed method

• Atomic force microscopy (AFM) to visualize micro-rip formation and evolution under strain.
• Electrical transport measurements to assess changes in conductivity and device performance during strain cycles.
• Mechanics simulations to model the strain distribution and rip dynamics in graphene.
• Application of controlled tensile strain on graphene devices suspended over elastomer substrates.
• Cycling of tensile strain to test the reversibility of rip opening and closing.
• Correlation of mechanical rippability with electronic transport recovery.

Experimental results

Research questions

• RQ1 How do micro-rips form in graphene during the initial application of tensile strain on elastomer substrates?
• RQ2 To what extent do rips in graphene reversibly open and close under repeated strain cycles?
• RQ3 How does the initial strain-induced rippability affect the long-term electrical transport stability of graphene devices?
• RQ4 Can electrical transport properties recover elastically after mechanical rippability occurs?

Key findings

• Micro-rips form in graphene during the initial application of tensile strain on elastomer substrates.
• Subsequent strain cycles cause rips to reversibly open and close without permanent structural change.
• Initial tensile strain degrades device transport properties, but subsequent cycles cause only moderate, reversible degradation.
• Electrical transport properties recover elastically after strain relaxation, indicating high reversibility.
• Graphene devices maintain robust electrical performance despite partial mechanical failure due to rippability.
• The combination of rippability and reversible strain response enables durable electronic functionality in flexible devices.