We measured the elastic properties and intrinsic breaking strength of free-standing monolayer graphene membranes by nanoindentation in an atomic force microscope. The force-displacement behavior is interpreted within a framework of nonlinear elastic stress-strain response, and yields second- and third-order elastic stiffnesses of 340 newtons per meter (N m(-1)) and -690 Nm(-1), respectively. The breaking strength is 42 N m(-1) and represents the intrinsic strength of a defect-free sheet. These quantities correspond to a Young's modulus of E = 1.0 terapascals, third-order elastic stiffness of D = -2.0 terapascals, and intrinsic strength of sigma(int) = 130 gigapascals for bulk graphite. These experiments establish graphene as the strongest material ever measured, and show that atomically perfect nanoscale materials can be mechanically tested to deformations well beyond the linear regime.

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Measurement of the Elastic Properties and Intrinsic Strength of Monolayer Graphene

https://www.bc.edu/content/dam/files/schools/cas_sites/physics/pdf/Ren/p85.pdf

Advances in the science and technology of carbon nanotubes and their composites: a review

Photoinduced reactivity of titanium dioxide

Department of Materials Science, University of Patras, 26504 Rio Patras, Greece, Theoretical and Physical Chemistry Institute, National Hellenic Research Foundation, 48 Vass. Constantinou Avenue, 116 35 Athens, Greece, Institut de Biologie Moleculaire et Cellulaire, UPR9021 CNRS, Immunologie et Chimie Therapeutiques, 67084 Strasbourg, France, and Dipartimento di Scienze Farmaceutiche, Universita di Trieste, Piazzale Europa 1, 34127 Trieste, Italy

Chemistry of Carbon Nanotubes

Small but strong: A review of the mechanical properties of carbon nanotube–polymer composites

Nanocrystal Shape Control: Synthesis and Structure–Property Correlation in Shape‐Controlled ZnO Nanoparticles Prepared by Chemical Vapor Synthesis and their Application in Dye‐Sensitized Solar Cells (Adv. Funct. Mater. 6/2009)

Results of UV irradiation experiments in vacuum on SWNTs and peapods, as followed by in-situ Raman spectroscopy with increasing laser power up to 300 mW are reported. UV micro-Raman measurements were used to record spectra free of black-body radiation. Photon absorption was found to induce both the shifting and broadening of the G+ and G- bands. The local temperature increase (up to a temperature gain of ∼1000 K) was able to be reliably calculated from the band feature variation, more specifically considering the G+ band. Meanwhile, a specific sensitivity to oxidation of the nanotubes from peapods was revealed, due the fullerene-catalysed dissociation of molecular oxygen traces into active species. In addition, both silica and diamond substrates were used. The different thermal conductivity of the substrates has the effect of changing the laser power levels needed to induce structural transformations. Carrying-out UV irradiation of nanotube-based material while monitoring the induced temperature via in situ Raman spectroscopy therefore appears as a new tool likely to be useful for the nano-engineering of nanotube-based devices.

Thermal transfer in SWNTs and peapods under UV-irradiation

Carbon nanotubes epoxy composites have been processed with high power laser pulses and micro-machined with a single crystal diamond tool. The effect of the dispersion of the carbon nanotubes (CNTs, 0.4 wt %) in the epoxy resin and carbon nanotube interaction with the composite matrix have been probed using spectroscopic Raman mapping. While the micro-machined surface maintains a good electrical conductivity after machining, the surface is poorly conductive after laser ablation. Laser processing (power 150 J/pulse, 1064 nm) transforms the surface of the carbon nanotube nanocomposite up to a distance of 25 µm. AFM images show that the diamond machined surface reduces the composite surface roughness.

Laser Induced Modifications of Carbon Nanotube Composite Surfaces

Optics Near Surfaces and at the Nanometer Scale

We find that functionalized SWCNT and DWCNT's (mainly double wall carbon nanotubes) in composites, DWCNTs under hydrostatic pressure and blue illuminated DWCNTs in methanol show the same up shift of the Raman G band and the appearance of a new band at 1455cm−1. This is attributed to the interaction of the CH3 group of the amphiphilic molecule in composites or the CH3 group of alcohol with the outer tube of DWCNT's and indicates that laser heating of DWCNT's in methanol can induce the chemical adsorption of CH3 onto the CNT (carbon nanotube) surface.

https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S1946427400076922

Revathi Bacsa

Papers

Nanocrystal Shape Control: Synthesis and Structure–Property Correlation in Shape‐Controlled ZnO Nanoparticles Prepared by Chemical Vapor Synthesis and their Application in Dye‐Sensitized Solar Cells (Adv. Funct. Mater. 6/2009)

Thermal transfer in SWNTs and peapods under UV-irradiation

Laser Induced Modifications of Carbon Nanotube Composite Surfaces

Optics Near Surfaces and at the Nanometer Scale

Enhanced Raman signal of CH3 on carbon nanotubes