Phononic Thermal Transport along Graphene Grain Boundaries: A Hidden Vulnerability
12
Citation
43
Reference
10
Related Paper
Citation Trend
Abstract:
Abstract While graphene grain boundaries (GBs) are well characterized experimentally, their influence on transport properties is less understood. As revealed here, phononic thermal transport is vulnerable to GBs even when they are ultra‐narrow and aligned along the temperature gradient direction. Non‐equilibrium molecular dynamics simulations uncover large reductions in the phononic thermal conductivity ( κ p ) along linear GBs comprising periodically repeating pentagon‐heptagon dislocations. Green's function calculations and spectral energy density analysis indicate that the origin of the κ p reduction is hidden in the periodic GB strain field, which behaves as a reflective diffraction grating with either diffuse or specular phonon reflections, and represents a source of anharmonic phonon–phonon scattering. The non‐monotonic dependence with dislocation density of κ p uncovered here is unaccounted for by the classical Klemens theory. It can help identify GB structures that can best preserve the integrity of the phononic transport.Keywords:
Vulnerability
This Special Issue compiles a set of innovative developments on the use of graphene-based materials in the fabrication of sensors. In particular, these contributions report original studies on a wide variety of sensors, such as gas sensors for NO2 or NH3 detection, antibody biosensors or mass sensors. All these devices have one point in common: they have been built using graphene-based materials like graphene, graphene oxide, reduced graphene oxide, inkject printing graphene, graphene-based composite sponges, graphene screen-printed electrodes or graphene quantum dots.
Cite
Citations (47)
Graphene oxide can be used as a precursor to graphene, but the quality of graphene flakes is highly heterogeneous. Scanning Raman microscopy (SRM) is used to characterize films of graphene derived from flakes of graphene oxide with an almost intact carbon framework (ai-GO). The defect density of these flakes is visualized in detail by analyzing the intensity and full width at half-maximum of the most pronounced Raman peaks. In addition, we superimpose the SRM results with AFM images and correlate the spectroscopic results with the morphology. Furthermore, we use the SRM technique to display the amount of defects in a film of graphene. Thus, an area of 250 × 250 μm2 of graphene is probed with a step-size increment of 1 μm. We are able to visualize the position of graphene flakes, edges and the substrate. Finally, we alter parameters of measurement to analyze the quality of graphene in a fast and reliable way. The described method can be used to probe and visualize the quality of graphene films.
Cite
Citations (85)
This chapter contains sections titled: Introduction Preparation of Graphene Oxide by Modified Hummer's Method Dispersion of Graphene Oxide in Organic Solvents Paper-Like Graphene Oxide Thin Films of Graphene Oxide and Graphene Nanocomposites of Graphene Oxide Graphene-Based Materials Graphene-Like 2D Materials Conclusion
Graphene foam
Cite
Citations (8)
Graphene sheets was a fascinating material with its tantalizing applied foreground.A prerequisite for exploiting most proposed applications for graphene was to seek for a method that readily and simply produced graphene sheets in large quantities.By far,graphene sheets can be prepared by three techniques in general.Among them,oxidation and reduction processing graphene sheets was the most suitable for producing graphene sheets in large quantity.XRD,transmission electron microscopy and FT-IR spectra analysis indicated that graphene single sheets were readily synthesized through the chemical processing.Moreover,the crystal structure of the graphene nanosheets was maintained intact after chemical functionalisation.
Graphene foam
Cite
Citations (0)
The authors investigated the influence of substrates on Raman scattering spectrum from graphene. The room-temperature Raman signatures from graphene layers on GaAs, sapphire, and glass substrates were compared with those from graphene on the standard Si∕SiO2 (300nm) substrate, which served as a reference. It was found that while G peak of graphene on Si∕SiO2 and GaAs is positioned at 1580cm−1, it is downshifted by ∼5cm−1 for graphene on sapphire and, in some cases, splits into doublets for graphene on glass with the central frequency around 1580cm−1. The obtained results are important for nanometrology of graphene and graphene-based devices.
Bilayer graphene
Cite
Citations (248)
He notes that, since graphene's discovery, scientists working with natural graphite to produce graphene have used what is known as the Hummers method to turn graphene oxide into reduced graphene oxide (or rGO - a term which [Gordon Chiu] says has been incorrectly and interchangeably used with the term'graphene').
Because graphite has the same composition and arrangement as graphene, natural graphite is a popular and cost-effective precursor in the production of many graphene materials, including graphene nanoplatelets, reduced graphene and graphene oxide, Dr Elena Polakova, CEO of Graphene Laboratories told IM.
In order to restore some of graphene's natural properties - because graphene oxide is not conductive like graphene - we reduced the samples to create reduced graphene oxide. We then went a step further and converted the reduced graphene oxide into a paste with applications in conductive inks and coatings.
Graphite oxide
Graphene foam
Cite
Citations (2)
Graphene 基于 graphene 有唯一的物理性质，和许多 proof-of-concept 设备是 demonstated。因为，为 graphene 的申请的一个前提是它以一种控制方式的生产在这些层的 graphene 层和缺点的数字显著地影响运输性质。在这份报纸，我们简短在 graphene 和基于 graphene 的 composites 的控制合成上考察我们的最近的工作，方法到的发展在干净精力应用并且为定序的快速的 DNA 描绘 graphene 的 graphene 层，和使用。例如，我们使用了钻电子光谱学描绘 graphene 层的数字和结构，在整个 Ni 电影底层上的生产单个层的 graphene，是的综合分散得好的减少的 graphene 氧化物一致地有唯一的金 nanodots 的 grafted，和制作 graphene nanoscrolls。我们也在器官的太阳能电池并且直接探索了 graphene 的应用，定序的 ultrafast DNA。最后，我们探讨挑战那 graphene 在它的合成和干净精力和生物察觉到应用的静止的脸。
Graphene foam
Bilayer graphene
Nanodot
Cite
Citations (0)
Graphene foam
Cite
Citations (253)
Orthotropic material
Cite
Citations (0)
Graphene-based materials used in electrosorption: (1) 3D graphene; (2) graphene/MO; (3) graphene/carbon composites; (4) heteroatom-doped graphene; (5) graphene/polymer-based.
Heteroatom
Graphene foam
Carbon fibers
Cite
Citations (11)