# Graphene synthesis: templates

> Graphical abstracts of the main routes to graphene: top-down exfoliation and oxidation of graphite, and bottom-up growth on metals and SiC.

URL: https://www.labcanvas.com/templates/graphene-synthesis

11 templates. All templates: https://www.labcanvas.com/templates

- [Mechanical exfoliation with adhesive tape](https://www.labcanvas.com/templates/graphene-synthesis/mechanical-exfoliation-scotch-tape-graphene) ([Markdown](https://www.labcanvas.com/templates/graphene-synthesis/mechanical-exfoliation-scotch-tape-graphene.md)): Graphene was first isolated by peeling graphite with ordinary adhesive tape. Repeated peeling thins the flakes on the tape, which is then pressed onto an oxidized silicon wafer, where single layers are spotted by their faint optical contrast and confirmed by Raman spectroscopy or AFM.
- [Liquid-phase exfoliation of graphite](https://www.labcanvas.com/templates/graphene-synthesis/liquid-phase-exfoliation-graphene) ([Markdown](https://www.labcanvas.com/templates/graphene-synthesis/liquid-phase-exfoliation-graphene.md)): Graphite is split into thin sheets directly in a liquid. The layers are first loosened by expansion and solvothermal intercalation, then torn apart by ultrasound in a solvent whose surface energy matches graphene, such as NMP. Centrifugation removes the thick flakes and leaves stable dispersions of few-layer graphene.
- [Graphene oxide: synthesis and characterization](https://www.labcanvas.com/templates/graphene-synthesis/graphene-oxide-synthesis-characterization) ([Markdown](https://www.labcanvas.com/templates/graphene-synthesis/graphene-oxide-synthesis-characterization.md)): A six-panel figure on graphene oxide: the modified Hummers' route from graphite through graphite oxide and GO to reduced GO, the Lerf–Klinowski structural model with its oxygen groups, and representative XRD, Raman, FTIR and XPS C 1s spectra comparing graphite, GO and rGO.
- [Doped carbon nanosheets from layered biochar](https://www.labcanvas.com/templates/graphene-synthesis/doped-carbon-nanosheets-layered-biochar) ([Markdown](https://www.labcanvas.com/templates/graphene-synthesis/doped-carbon-nanosheets-layered-biochar.md)): A layer-by-layer precursor of alternating inorganic and organic layers is carbonized in place, and the inorganic template is then leached out with acid. Liquid-phase exfoliation splits the resulting multilayered biochar into thin, porous carbon nanosheets co-doped with Fe, N and S, used as oxygen-reduction catalysts and supercapacitor electrodes.
- [Electrochemical exfoliation of graphite](https://www.labcanvas.com/templates/graphene-synthesis/electrochemical-exfoliation-graphene) ([Markdown](https://www.labcanvas.com/templates/graphene-synthesis/electrochemical-exfoliation-graphene.md)): A graphite electrode is made the anode in an aqueous salt solution such as ammonium sulfate. Under a DC bias, sulfate anions and water enter the graphite edges and the gases they produce force the layers apart, so few-layer graphene flakes detach into the electrolyte. The flakes are filtered, washed and re-dispersed.
- [Hummers method: graphite to GO to rGO](https://www.labcanvas.com/templates/graphene-synthesis/hummers-method-graphene-oxide-rgo) ([Markdown](https://www.labcanvas.com/templates/graphene-synthesis/hummers-method-graphene-oxide-rgo.md)): Graphite is oxidized in concentrated sulfuric acid with sodium nitrate and potassium permanganate, diluted with water, treated with hydrogen peroxide and sonicated into graphene oxide (GO) sheets. Reducing the GO, for example with hydrazine hydrate or sodium borohydride, removes most of the oxygen groups and gives reduced graphene oxide (rGO).
- [Improved Hummers method with K₂FeO₄](https://www.labcanvas.com/templates/graphene-synthesis/improved-hummers-method-k2feo4) ([Markdown](https://www.labcanvas.com/templates/graphene-synthesis/improved-hummers-method-k2feo4.md)): A NaNO₃-free variant of the Hummers method in which potassium ferrate (K₂FeO₄) takes over part of the oxidizing work of KMnO₄. Graphite is intercalated and oxidized in sulfuric acid in two stages, then diluted with hot water to give graphene oxide.
- [CVD growth of graphene on copper and nickel](https://www.labcanvas.com/templates/graphene-synthesis/cvd-graphene-growth-copper-nickel) ([Markdown](https://www.labcanvas.com/templates/graphene-synthesis/cvd-graphene-growth-copper-nickel.md)): In chemical vapour deposition, methane breaks down on a hot metal foil and its carbon assembles into graphene. Copper dissolves almost no carbon, so growth happens on the surface and stops once one layer covers the foil. Nickel dissolves carbon at the growth temperature and releases it as it cools, giving few-layer graphene whose thickness depends on the cooling rate.
- [CVD graphene on copper and PMMA transfer](https://www.labcanvas.com/templates/graphene-synthesis/cvd-graphene-pmma-transfer) ([Markdown](https://www.labcanvas.com/templates/graphene-synthesis/cvd-graphene-pmma-transfer.md)): Graphene grown by CVD on copper foil has to be moved onto an insulating substrate before it can be used in devices. A thin PMMA film is spin-coated on top as a support, the copper is etched away so that the PMMA/graphene film floats, and the film is scooped onto SiO₂/Si; acetone then dissolves the PMMA.
- [Epitaxial graphene on SiC](https://www.labcanvas.com/templates/graphene-synthesis/epitaxial-graphene-sic) ([Markdown](https://www.labcanvas.com/templates/graphene-synthesis/epitaxial-graphene-sic.md)): Graphene can be grown directly on a silicon carbide wafer, with no transfer. Hydrogen etching first leaves clean, regular atomic terraces. Heating in argon then drives silicon off the surface so that the carbon left behind forms graphene nuclei, and adding methane lets these nuclei grow into a continuous layer.
- [Graphene on SiC for remote epitaxy and layer transfer](https://www.labcanvas.com/templates/graphene-synthesis/graphene-remote-epitaxy-layer-transfer) ([Markdown](https://www.labcanvas.com/templates/graphene-synthesis/graphene-remote-epitaxy-layer-transfer.md)): Epitaxial graphene on SiC can serve as a reusable growth template. A single-crystal GaN film is grown on the graphene, a nickel stressor layer and tape are added, and the film peels off cleanly along the weak graphene interface. It is then placed on any host substrate, while the graphene/SiC wafer goes back for the next growth.